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Source Tech Revolution pg. 90

Mech Overview

Source Tech Revolution pg. 92
Mechs are immense robots that combine armor, agility, and firepower into one devastating package piloted by one or more operators. In Starfinder, mechs represent powerful tools for PCs to confront far mightier foes than they could unaided. PCs might custom-build their own mechs, salvage the technology in the field, or pilot mechs provided by powerful patrons.

Building And Using Mechs

Source Tech Revolution pg. 92
Building Mechs (page 96) provides a system for constructing custom mechs and presents a wide array of options for players to customize their machine’s size, armaments, limbs, and more. The section also presents rules for multiple PCs to build an assembled mech, each create their own single-pilot mech, or split between several machines in any combination.
Mech combat (page 112) is a flexible system. Mechs use many of the existing rules for Starfinder, allowing players to jump into mech combat with ease, whether they’re taking on titanic creatures, clashing with enemy mechs, or fighting off entire squads of foes single-handedly. Unlike powered armor, which functions as an extension of the operator’s body that deflects attacks rather than absorbs damage, a mech functions more like a specialized vehicle that’s piloted by one or more operators. A mech has its own defenses and Hit Points, shielding its operators from harm while they give the mech commands (see page 98 for more information on mech statistics). Mech weapons (page 102) are in a class of their own, far exceeding in scale any armaments sized for PCs.
Much as with starships, acquiring or using mechs does not cost the PCs credits (in a typical campaign, mechs are not available for sale), and Starfinder campaigns can thrive with any amount of mech combat, from mech encounters every session to no mech combat whatsoever—the exact prevalence of mech encounters can be tailored to the campaign’s needs and is ultimately up to the GM to decide. Mechs provide a significant power advantage that make many otherwise challenging encounters trivial, so GMs should consider being purposeful on their inclusion—such as a means to overcome impossible odds or insurmountable foes—rather than to simply trivialize challenges the PCs face.


Source Tech Revolution pg. 92
Some groups playing in a mech-themed campaign might want several of their individual mechs to be able to combine into a larger, amalgamated mech that they can copilot as a party. If you decide that this fits your campaign, you can allow the PCs to design two sets of mechs (using the rules for building mechs starting on page 96): the individual, component mechs; and a singular mech to represent the assembled mech, which uses all the party’s Mech Points. The assembled mech should feature the weapons and systems of its component mechs, and its frame should be the same size category as the largest component mech.
Combining several mechs into an assembled mech (or disassembling an assembled mech into its component mechs) should generally take place only outside of combat; if the GM allows for in-combat mech assembly or disassembly, it takes at least one round.
Damage dealt to an assembled mech is carried over to its component mechs when it disassembles, and damage dealt to component mechs carries over to an assembled mech when they combine. To represent this, convert the mechs’ current HP to a percentage of total HP (rounding down to the nearest 10%) and apply it to the assembled or disassembled forms. For example, if three component mechs have a maximum collective total of 75 HP and have a collective current HP of 35, the mech they assemble into should have 50% of its total HP. If that assembled mech takes damage that reduces it to 40% of its total HP and then disassembles, the three component mechs should have a collective current HP of 40% (or 30) HP, divided among them such that no individual mech regains Hit Points from assembling or disassembling.

Sample Mechs

Source Tech Revolution pg. 92
Pages 112–119 present more than a dozen examples of mechs from cultures across the galaxy, such as the Azlanti Imperator Pinion, the Daimalko Valkor, the Idaran Breacher, and the Veskarium’s Warmander. The mechs detailed there are of course just examples; far stranger and rarer models are manufactured across the galaxy, as well as near-infinite custom-built mechs found throughout the Starfinder setting.

Designing Mech Encounters

Source Tech Revolution pg. 92
Mech combat uses the same rules and functions on the same scale as most other Starfinder combats, such as using square-grid maps, means of resolving attacks, and more. As a result, designing encounters involving mechs is not substantially different from designing any other combat encounter. The following are some things to consider when designing encounters for mechs.
CR: PCs that are operating mechs appropriate for their level have an Average Party Level 3 levels higher than normal, and therefore are able to overcome stronger threats as a result; consider the following when designing encounters for mechs: First, mechs with multiple operators are typically highly maneuverable, capable of both moving and attacking skillfully. As such, slow-moving foes with limited ranged options are less threatening for PCs operating mechs that can often run circles around them. When presenting a small number of foes, consider favoring maneuverable or long-range combatants, or consider providing terrain or objectives that encourage the PCs to engage the enemy at close range.
Second, many mech weapons excel at attacking multiple targets at once, so mechs excel at fending off large numbers of lesser foes. Enemies whose CR are lower than the mech’s tier rarely pose a threat to the mech, unless they’re in large groups. However, using only a few mechs to defeat a small army (or a large foe with numerous minions) can be extremely gratifying.
Experience: Even though the PCs can overcome much more powerful threats than usual in a mech, mech encounters should provide a similar amount of experience to encounters appropriate for the PCs’ APL. Combat encounters the PCs overcome while using mechs typically grant experience points as though the CR of each challenge were 3 lower than usual. Do not reduce the experience points earned from challenges that aren’t substantially affected by the PCs’ access to mechs, such as story awards for performing heists or overcoming encounters without mech combat.
Space: Mechs are big. Huge mechs may be able to navigate conventional adventure spaces, but Gargantuan and Colossal mechs require a larger area to maneuver and fight effectively. When creating mech encounters, aim to provide each mech at least four times as much area to maneuver in than the mech occupies, and make sure any paths, halls, or other passageways are large enough to accommodate all of the combatants. Alternatively, if the goal is to create an encounter where the mech is forced to struggle to maneuver or engage foes due to restrictive terrain, consider treating the encounter’s Challenge Rating as at least 1 lower. An encounter in which the PCs fight an immense foe by exploiting claustrophobic terrain can offer fun tactical challenges!
NPC Mechs: Nonplayer character mechs are built using a different set of guidelines to provide a balanced encounter for player characters. See page 109 for advice on building NPC mechs.


Source Tech Revolution pg. 93
Another exciting possibility for mechs is giving them the ability to transform between a mech and a vehicle form. If this functionality fits the role of mechs in your campaign, you can allow for one or more vehicles obtained by the PCs (such as through purchases or adventure rewards) to transform into one or more mechs. Transforming mechs should be no more than one size category larger than their vehicle form (for example, a Huge vehicle might transform into a Huge or Gargantuan mech).
As with assembling mechs (page 92), such involved transformation should generally take place only outside of combat, and damage sustained in either mech or vehicle form should be retained between forms. As described in the Assemble! sidebar, convert HP to a percentage of total each time a transformation occurs and ensure that no mech or vehicle regains Hit Points merely by transforming. Effects that restore Hit Points to vehicles don't function on vehicles that can transform into mechs.

Building Mechs

Source Tech Revolution pg. 94
Mechs show up in a wide range of forms and functions, not only varying by manufacturer but also as a result of their crew, faction, or world of origin. Regardless of the wide variety of appearances or particular abilities, mechs all share a set of statistics that govern their operation, and any number of different mechs can be built following the same step-by-step process.

Understanding Mechs

Source Tech Revolution pg. 96
Mechs and their base frames are described using stat blocks that include a number of pieces of information. Each statistic listed in a mech or mech frame statblock is defined below. Explanations for how to calculate a mech’s various statistics appear in the final step of Building a Mech (pages 97–98).
  • Tier: A mech’s tier represents its overall power level, impacts its statistics, and determines many options when building mechs.
  • Size and Frame: A mech’s frame determines its size category and informs its statistics. It might have an attribute in parentheses (such as flight) that informs other options.
  • Operators: Each mech can accommodate a certain number of operators. A mech can’t function unless it has at least the minimum number of operators required and can’t accommodate more operators than this range’s maximum value.
  • Power Points (PP): A mech’s power core (see below) provides it with a certain number of Power Points, which can be used to power auxiliary systems, perform special abilities (page 113), and more. The mech’s initial PP is noted, with the rate at which PP regenerates each turn and a maximum PP listed in parentheses.
  • Speed: This is the mech’s land speed (based on its frame), followed by any additional speeds and types of movement the mech has.
  • Slots: Each mech frame has frame slots and auxiliary (aux) slots. Frame slots allow mounting weapons, and aux slots can each accommodate one auxiliary system. Some limbs also grant slots for weapons; lower limbs and upper limbs grant lower limb slots and upper limb slots, respectively. A mech can’t equip more weapons or auxiliary systems than it has corresponding slots.
  • Senses: This lists the mech’s special senses. Most mechs have at least low-light vision, darkvision with a range of 120 feet, and blindsense (vibration) with a range of 30 feet.
  • Hit Points (HP): This is the total amount of damage a mech can take before it becomes inoperable. If a mech takes twice this amount of damage, it is destroyed.
  • Shield Points (SP): Mechs project personal force shields that dampen incoming damage, represented by Shield Points (SP), which function in many ways like temporary Hit Points (see Taking Damage on page 114 for more information).
  • Hardness: Most mechs have a hardness value (Starfinder Core Rulebook 409), determined by their frame and tier, that reduces incoming damage they take.
  • EAC and KAC: A mech’s Energy Armor Class and Kinetic Armor Class is determined by its tier, frame, and limbs.
  • Saving Throw Bonuses: Some mech frames provide the mech a bonus to Fortitude and/or Reflex saving throws.
  • Immunities: Mechs have the construct immunities universal creature rule (Alien Archive 153).
  • Attack Bonus: Each mech has a bonus added to its attack rolls, based on its tier.
  • Weapons: A mech’s stat block lists the melee and ranged weapons installed in its frame slots. Each weapon lists its weapon slot, damage, and any special properties.
  • Space and Reach: This lists the mech’s space and reach, which are based on its size category. A Huge mech’s reach is 15 feet, a Gargantuan mech’s reach is 20 feet, and a Colossal mech’s reach is 30 feet.
  • Strength: A mech doesn’t have ability scores, but it does have an effective Strength modifier, based on its frame and tier, for calculating its melee damage modifiers, resolving Strength checks to break objects, and determining its carrying capacity (see Other Mech Features below).
  • Power Core: This is the source of a mech’s energy and Power Points (see above). If a power core has a power core template (page 102) applied, that is listed in parentheses.
  • Lower Limbs and Upper Limbs: A mech’s limbs modify a variety of the mech’s statistics and might grant additional movement options. Upper limbs are listed with their attack bonuses in parentheses.
  • Auxiliary Systems: These systems augment a mech’s capabilities and might grant it additional abilities.
  • Upgrades: These are a mech’s miscellaneous upgrades, representing further specialization of a mech’s technology. Any adjustments to a mech’s statistics are already included in its stat block.
  • Cost: The Mech Point cost for the frame, which is determined by the mech’s tier.

Other Mech Features

Source Tech Revolution pg. 96
The following apply to all mechs.
Carrying Capacity: A mech can carry its equipment, operators, cargo hold contents, and small loads without tracking carrying capacity. A mech becomes encumbered when carrying an amount of bulk equal to or greater than 20 × its Strength modifier and becomes overburdened when carrying an amount of bulk equal to or greater than 40 × its Strength modifier.
Computer: A mech houses a personal comm unit and a tier 1 computer that primarily coordinates the mech’s movements and systems. The computer’s tier increases by 1 at mech tier 4 and every 4 tiers thereafter. The superior computer upgrade (page 108) can enhance the computer’s performance.

Building A Mech

Source Tech Revolution pg. 97
This section details the steps to creating a customized mech. No matter the size, form, or intended function, each mech is created using the same process, which involves purchasing features such as frames, limbs, and armaments that modify the mech’s statistics, provide additional actions, or augment the mech’s functions. The result could be an agile skirmisher, an armor-plated quadruped brimming with missiles, or many other possibilities.
A mech sheet is provided on page 165.

Step 1: Conceptualize

Source Tech Revolution pg. 97
Start by deciding what kind of mech you’re designing, with a general idea of its purpose and required number of operators.

Step 2: Allocate Mech Points

Source Tech Revolution pg. 97
As a group, your party has a pool of Mech Points (MP) with which to create one or more mechs, with each PC contributing a number of points to the pool based on their level (see Table 4–1: Mech Points per PC, below). The group can then pool or divvy up these MP as they see fit to create one or more mechs, whether it be a single-pilot mech for each PC, one assembled mech for the whole party (page 92), or a combination of mechs in between. No one mech can be built using more than three times the MP of any other mech in the group.
The party determines a mech’s tier based on the number of MP they assign to the mech (see Table 4–2: Minimum Mech Points below for the minimum number of MP required to build a mech of a given tier). The mech’s tier can’t exceed the party’s Average Party Level (APL) by more than 1.
For example, a group of four 5th-level PCs would have a total of 300 MP and an APL of 5. They could create one mech with the 300 MP, and although its maximum tier would be 6, the PCs would have lots of leftover MP to spend on additional features for it. Alternatively, they might create three tier-5 mechs. If each PC wanted their own single-pilot mech, they might instead split the MP evenly, each spending 75 MP to create their own tier-4 mech.
At the GM’s discretion, the mechs the PCs build might be more or less powerful than these guidelines suggest.

Table 4-1: Mech Points per PC

PC LevelMP Per PC

Table 4-2: Minimum Mech Points

Mech TierMinimum MP

Step 3: Select Frame

Source Tech Revolution pg. 97
Each mech has a frame, a reinforced torso that houses its power core, operators, and various systems. A mech’s frame determines its size category, crew complement, Hit Points, frame slots, auxiliary slots, speed, EAC, KAC, and hardness. Each frame costs a number of MP based on the mech’s tier. Frames are listed beginning on page 98.

Step 4: Select Limbs

Source Tech Revolution pg. 97
Each mech includes a set of upper limbs and lower limbs. Unless your mech has a special ability that allows it to install an exceptional number of limbs, each mech includes only one set of upper limbs and one set of lower limbs, and each set can affect the mech’s Hit Points, speed, weapon slots, attack modifiers, EAC, and KAC. Upper limbs and lower limbs are listed on page 101.

Step 5: Select Power Core

Source Tech Revolution pg. 97
A mech’s power core determines how much power it can store and generate, measured in Power Points (PP), which allow the mech to perform exceptional actions. Power cores are listed on page 102.

Step 6: Select Weapons

Source Tech Revolution pg. 97
A mech can mount as many weapons as it has frame slots, upper limb slots, and lower limb slots. A weapon’s level determines its damage and MP cost; each weapon also gains a simple template based on its type that can affect its damage, range, and special abilities. A mech must either mount or hold any weapons in its available weapon slots. Weapons are listed starting on page 103.

Step 7: Select Auxiliary Systems

Source Tech Revolution pg. 97
Each mech frame provides auxiliary slots, each of which can accommodate one auxiliary system to provide additional capabilities. These systems don’t cost additional MP. Auxiliary systems are listed beginning on page 106.

Step 8: Select Upgrades

Source Tech Revolution pg. 97
If you have leftover Mech Points, you can spend them on miscellaneous upgrades, such as a frame reinforcement that provides additional HP or an enhancement to the mech’s speed. Upgrades are listed on page 108.

Step 9: Add Details

Source Tech Revolution pg. 97
Finally, determine your mech’s remaining statistics using the information in Mech Statistics (page 98) and record them on the mech sheet (page 165). You might also want to give your mech a name, quirks, a physical description, and so on.

Mech Statistics

Source Tech Revolution pg. 98
Use the following table and formulas to generate a mech’s statistics. Note that some mech components, such as upgrades, might further modify these statistics.
Hit Points (HP)
Base HP from frame and limbs + (Hit Point Advancement from frame and limbs × tier)
Shield Points (SP)
See Table 4–3.
Hardness from frame + hardness bonus (see Table 4–3)
Armor Class
Base AC (see Table 4–3) + bonuses from frame and limbs
Saving Throws
Base save bonus (see Table 4–3) + bonuses from frame and lower limbs
Attack Bonus
Base attack bonus (see Table 4–3) + the operator’s base attack bonus or ranks in the Piloting skill + bonuses from upper limbs
Damage Modifier
Tier (+ Strength modifier [see Table 4–3] for melee attacks)
Strength Modifier
Strength modifier (see Table 4–3) + bonus from frame

Table 4-3: Mech Statistics by Tier

TierSPHardness BonusBase ACBase Save BonusBase Attack BonusStrength Modidier


Source Tech Revolution pg. 98
A mech’s armored torso comprises its frame, which not only houses essential machinery but also determines the mech’s size and the number of operators it can accommodate. A mech’s frame also affects many of its statistics, such as EAC, KAC, and hardness. Each frame’s cost is based on the mech’s tier. The base frames that follow are organized by category.

Lower Limbs

Source Tech Revolution pg. 101
A mech’s lower limbs typically take the form of legs, though hover pads and tank treads are common alternatives. A mech is limited to a single set of lower limbs. Lower limbs modify a variety of the mech’s statistics and might grant additional movement options or provide additional uses for Power Points.

Upper Limbs

Source Tech Revolution pg. 101
A mech’s upper limbs typically represent a pair of arms, though they can be found in other forms, such as multiple limbs or even mechanical tentacles. A mech is limited to a single set of upper limbs. Upper limbs modify a variety of the mech’s statistics and may provide additional uses for Power Points.
Some upper limbs have attack modifiers marked with an asterisk (*). Choose either the melee or ranged attack modifier and increase it by 1 when you purchase these upper limbs.

Power Core

Source Tech Revolution pg. 102
A mech’s power core generates all the energy necessary to pilot the mech and operate its major functions. Each power core also generates some excess energy, measured as Power Points (PP; see page 113), which an operator can expend to enhance the mech’s performance and execute extraordinary maneuvers. Each power core has: a rate, representing the number of PP it generates at the end of its turn; an initial value, representing the number of PP a mech has when it begins an encounter; and a maximum (shown in parentheses), representing the maximum PP the core can store during combat. A mech can use only a single power core.
Optionally, a power core can acquire one power core template that modifies some of its statistics or provides additional ways to generate or use Power Points.

Cost: A mk 0 power core (dynamo or eternal) is free. Every other power core costs a number of MP equal to the power core’s mk rating multiplied by the mech’s tier. For example, a mk 3 eternal core for a tier 9 mech costs 27 MP.

Table 4–4: Power Cores

Power CoreRateInitial (Maximum)
Dynamo, mk 020 (5)
Dynamo, mk 121 (6)
Dynamo, mk 231 (7)
Dynamo, mk 332 (8)
Dynamo, mk 443 (9)
Eternal, mk 014 (8)
Eternal, mk 115 (10)
Eternal, mk 216 (13)
Eternal, mk 327 (15)
Eternal, mk 429 (18)


Source Tech Revolution pg. 102
Engineers have designed and adapted a wide range of weapons for mechs to use. Each weapon combines two factors—the weapon’s level and a weapon template—to determine its statistics and MP cost. Mech weapons use many of the same rules as standard weapons (Core Rulebook 168), including damage types, targeting Armor Class, damage, range, critical hits, capacity, usage, and weapon special properties.
Mech weapons also use the following key statistics.
Level: This denotes the weapon’s relative power. A mech can’t use a weapon with a level that exceeds its tier by more than 1.
Weapon Template: Each weapon uses a weapon template that determines the weapon’s basic shape and functions, such as a laser cannon or sword. A weapon template modifies some combination of the weapon’s statistics, such as damage, damage type, range, and special weapon properties.
Damage: Each weapon deals low, medium, high, or extreme damage based on the weapon’s level when it successfully hits a target; see Table 4–5: Weapon Damage on page 104 for the damage dealt by weapons of a given level. A mech also adds its tier to the damage dealt by weapons it wields, and a mech adds its Strength modifier to its damage with melee weapons.
Slots: These are the number and types of slots that a mech must devote to equipping and wielding the weapon. Slot types include frame, lower limb, and upper limb.
Capacity: This is the number of attacks a mech can perform with the weapon before needing to reload as a move action. Each mech can carry two additional sets of ammunition, unless it has one or more ammo reserve auxiliary systems.
Power Point: Many weapons have a special ability that the mech can only perform by expending one or more Power Points; the number of PP used is listed in parentheses.
Cost: This is the cost of the weapon in MP. Each weapon’s cost is based on the weapon’s level.

Table 4-5: Weapon Damage

Level Low Damage Medium Damage High Damage Extreme Damage

Auxiliary Systems

Source Tech Revolution pg. 106
Auxiliary systems can provide mechs with an array of additional features, from augmenting the machine’s already impressive performance to granting completely unique abilities. Most auxiliary systems cost no Mech Points, but some systems have special requirements that a mech must fulfill to install them.

Mech Upgrades

Source Tech Revolution pg. 108
If you have leftover MP—which is especially likely for a mech with many operators—you can spend them on miscellaneous upgrades, representing further specialization of your mech’s technology. These options are relatively expensive for the benefit they provide, so it’s often best to upgrade a mech’s frame, limbs, and other features first.
Cost: These upgrades have a scaling cost. The first time a specific upgrade is purchased, use the listed cost. Each additional time the same upgrade is purchased for the mech, increase the upgrade’s cost per tier by 1; this increase is cumulative. For example, the fleet upgrade costs a number of Mech Points equal to 2 × the mech’s tier the first time it’s purchased, 3 × tier the second time, 4 × tier the third time, and so on.

Refitting And Upgrading Mechs

Source Tech Revolution pg. 108
In some campaigns, the PCs might have access to the same mechs over time. In this case, as the PCs’ character levels increase, so too do their mechs become more powerful, granting them additional Mech Points with which they can upgrade their machines (see Table 4–1: Mech Points per PC on page 97). These additional points could represent salvage gathered after their battles, an arrangement with a vendor who secures new gear for them, or even ongoing support from a military patron. The GM might require PCs to visit a safe workshop before spending these new MP—especially if the PCs perform major overhauls like replacing several mechs with one larger mech—but this process shouldn’t impact the campaign much.
In addition to gaining additional MP, gaining levels can increase the party’s Average Party Level, which can increase their mechs’ maximum tier. Increasing the tier can impact the mech’s attack modifiers, skill modifiers, Strength modifier, AC, and more.
Refitting Mechs: If the PCs want to change their mechs’ features before gaining additional MP (for example, replacing one auxiliary system with another that costs the same or fewer MP), they can do so at a safe workshop or other facility, given enough time. Refitting a component typically takes 4d6 hours, and refitting a mech’s frame typically takes 1d4 days. Completely changing or rebuilding a mech rarely takes more than a week.

Building NPC Mechs

Source Tech Revolution pg. 109
As a GM, you can create mech combatants to challenge the PCs using the rules in the Building a Mech section on page 97. When doing so, calculate a mech’s challenge rating by adding 2 to its CR if it has one operator, 3 to the CR if it has 2–3 operators, and 4 to the CR if it has 4 or more operators. Assume an operator’s Piloting ranks equal the mech’s tier. Be aware that mechs designed in this way have statistics best suited for PCs, and as a result, such mechs have fewer Hit Points, stronger defenses, lower attack bonuses, and slightly lower damage per attack than a creature of comparable CR.
As a recommended alternative, use the following rules to create NPC mechs that are both quicker to design and better designed for use as antagonists. These rules borrow many of the modifiers, values, and design recommendations from Appendix 1 of Starfinder Alien Archive, especially the Everything Is Optional sidebar on page 127. If you want a mech that feels faster, hardier, or deadlier, increase the appropriate statistics, and consider reducing a few other statistics to compensate.
Challenge Rating: Select the mech’s CR. Remember that PCs in their own mechs are much stronger, and an enemy mech’s CR must be approximately 3 higher than normal to provide an equivalent challenge.
Operators: Because a mech’s number of actions depends on its number of operators, an NPC mech’s statistics depend on its number of operators; a larger number of operators results in the mech having lower bonuses to compensate. Use the instructions below for a mech with 1 operator. For a mech with 2–3 operators, treat the mech’s CR as 2 lower for the purpose of calculating its attack bonuses. For a mech with 4–6 operators, treat the mech’s CR as 3 lower for the purpose of calculating its attack bonuses.
Statistics: Follow the instructions for building a creature, using the EAC, KAC, saving throw bonuses, attack bonuses, and ability DCs for a creature of the chosen CR. Use the skill bonuses for a creature whose CR is 3 lower than the mech’s CR. NPC mechs use the combatant array (Alien Archive 129–130).
Hit Points and Shield Points: Use the listed number of Hit Points for a creature whose CR is 2 lower than your mech’s CR. Give the mech a number of Shield Points equal to one-fifth the mech’s Hit Point total. Each turn, the mech regains a number of missing Shield Points equal to its CR.
Weapons and Damage: Rather than use the damage listed in the combatant array, give the mech several mech weapons (pages 102-106) whose levels are each 3 lower than the mech’s CR (minimum 1). A typical mech should have weapons whose combined Mech Point cost per level is approximately 9, providing it with about three weapons. Use the weapons’ level and type to determine their base damage dice, per Table 4–5: Weapon Damage on page 104. For ranged weapons, add the mech’s CR – 3 (minimum 0) as a damage modifier. For melee weapons, add an additional damage modifier of 5, representing the mech’s extraordinary strength.
Hardness: The mech has a hardness value equal to half its CR, rounded down.
Speed: A typical mech has a speed of 40 feet. Optionally, increase the mech’s speed by up to 40 feet, give the mech a fly speed of 60 feet (average), or a swim speed of 60 feet.
Power Points: A typical mech begins an encounter with 3 Power Points (page 113), regains 1 PP per turn, and can store a maximum of 5 PP.
Auxiliary Systems: The mech can select up to 4 auxiliary systems. Depending on the role the mech plays in the encounter, it might not need all of these systems. In general, limit the mech to one auxiliary system that’s restricted to a particular mech frame, such as a cloaker or teleporter.

Mech Combat

Source Tech Revolution pg. 112
mechs take multiple actions each round to move, attack, and activate abilities. See Chapter 8 of the Starfinder Core Rulebook for tactical combat rules.
The biggest differences in mech combat are size and action economy. Mechs are immense, capable of controlling large spaces, traveling quickly, and even affecting vast areas with their attacks. Mech control systems also allow multiple operators to act in concert, enabling many mechs to perform a host of actions on their turns.


Source Tech Revolution pg. 112
Mechs are designed to function seamlessly on the same battle maps of 5-foot-by-5-foot squares commonly used for Starfinder tactical combat. However, for mech encounters over larger areas or against larger foes, it works well to treat each of these squares as a 10-foot-by-10-foot area instead. Most mech size and distance values are divisible by 10; in rare cases where a range or size value is divisible by 5 but not by 10, round the value down to the nearest value divisible by 10. Thus, a Huge mech that would occupy a 15-foot-by-15-foot space would occupy a single square using a 10-foot scale, and a Huge mech’s reach would be 10 feet (one square) rather than 15 feet.

Mech Operators

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Each mech can accommodate one or more operators who share control over the mech’s movement, armaments, and other systems. Operators share a pool of actions and work together to control their machine (see Mech Actions below). Each mech requires a minimum number of operators to function and has a maximum number of operators it can accommodate.
A character can enter an allied or unattended mech in an adjacent space as a full action, becoming one of that mech’s operators. An operator can exit a mech as a full action, emerging into any empty space adjacent to the mech. At the GM’s discretion, an unattended mech can require an operator to succeed at a Computers check to hack it in order to initially gain control of that mech (DC = 20 + 1-1/2 × the mech’s tier).
A mech blocks line of effect to and from its operators. If a mech is destroyed (see Taking Damage on page 114), additional damage dealt to the mech is instead dealt to a random operator inside; that operator can attempt a DC 20 Reflex save to take half damage.

Statistics and Modifiers

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A mech’s actions represent a combination of its operators’ skill and its own sophisticated machinery, and some of the modifiers a mech uses when performing actions reflect this union. When an operator grants a mech an action, the mech uses that operator’s relevant bonus or skill ranks to help calculate the mech’s total modifier. If more than one operator contributes to the same action—such as two operators working together to grant their mech a full action—the mech uses the higher of the two operators’ statistics when calculating its modifier. See page 98 for how to calculate most of a mech’s statistics.
Initiative Modifier: A mech’s initiative modifier equals the lowest initiative modifier among its operators (minimum +0). A mech’s minimum initiative modifier increases by 1 at tier 5 and every 5 tiers thereafter.
Skill Modifiers: A mech’s skill check modifier equals 5 + half its tier; for Athletics checks, also add the mech’s Strength modifier. When an operator grants their mech an action and the mech performs a skill check as part of that action, the mech can use the operator’s ranks in that skill (instead of half the mech’s tier) to determine its modifier. When performing a Strength- or Dexterity-based skill check, a mech can instead use its operator’s ranks in Piloting to determine the mech’s skill modifier.

Mechs Aren’t Objects

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Unless otherwise specified, mechs do not count as objects for spells and abilities that affect objects.

Mech Actions

Source Tech Revolution pg. 112
A mech’s available actions per turn depend on the number of operators currently controlling it. While at least one operator is controlling it, a mech can take one move action per turn and one reaction per round.
Operators can take a full action to pilot a mech, granting it an additional move action or standard action that turn (maximum six additional actions per turn). A mech can perform a full action either in place of a standard and move action or in place of two standard actions. Regardless of its total number of actions, a mech can’t use more than two actions to move each turn, and it can’t activate any one mech component (such as a weapon or auxiliary system; see pages 102–108) more than once per round unless otherwise noted.
For example, if a mech has four operators, and each takes a full action to grant the mech actions, the mech can take up to four standard actions and one move action. The mech could use these actions to move its speed and attack once each with four different weapons. Alternatively, the mech could move its speed twice, attack once with one weapon, and make a full attack with another weapon. There are many other possible combinations, depending on the mech’s available systems.
Skills: A mech with at least one operator can take the appropriate action, if any, to attempt an Acrobatics, Athletics, or Perception skill check, or else an Intimidate check to demoralize. Some frames and auxiliary systems allow mechs to use additional skills; see page 112 for calculating a mech’s skill modifiers.
Guarded Step: When using the guarded step action, a mech can move up to 10 feet without provoking an attack of opportunity.

Power Points

Source Tech Revolution pg. 113
Each mech’s power core (page 102) provides it ample energy to move and fight while also generating excess power—measured in Power Points (PP)—that the mech can exploit to supercharge its systems. A mech’s power core determines how many PP it begins each encounter with, how many it can store at a time, and how many it generates at the end of each turn. Many auxiliary systems, weapons, and other components have special abilities that require expending PP to function.
In addition, several Power Points abilities available to all mechs can be used without spending actions. None of these abilities can be applied to the same check more than once.
Aim (1 PP): Before attempting an attack roll, the mech can activate this ability to roll 1d4 and add the result as an insight bonus to the attack roll.
Devastating Hit (3 PP): After hitting a creature with an attack, but before dealing damage, the mech increases its weapon’s damage value by one step against that creature (e.g. medium damage instead deals high damage). A weapon that already deals extreme damage instead adds 1 additional damage for every damage die rolled for the attack. This ability can’t be used for weapons that attack an intersection rather than a creature, such as weapons with the explode weapon special property.
Maneuver (1 PP): Choose one skill. Until the beginning of the mech’s next turn, operators add any insight bonuses they have that apply to that skill to the mech’s checks with that skill.
Replenish (2 PP): Activate this ability when regaining Shield Points. The number of SP the mech recovers increases by 1d8. This increases by an additional 1d8 at tier 5 and every 5 tiers thereafter.
Resist (1 PP): Before attempting a saving throw, the mech can activate this ability to roll 1d4 and add the result as a resistance bonus to the saving throw.

Special Mech Actions

Source Tech Revolution pg. 113
In addition to the actions detailed in Chapter 8 of the Core Rulebook, mechs can perform the following special actions.
Called Shot (Standard Action): The mech expends either 1 PP or 3 PP and makes an attack against a single mech. If the attack’s damage causes system damage, the operator can choose which component takes system damage, excluding the power core or cockpit; if the mech expended 3 PP, the operator can select any component to take the system damage.
Hurl (Full Action): The mech grabs a nearby object and throws it as a ranged attack with a range increment of 30 feet. The object can be, at largest, two size categories smaller than the mech. For an object of the maximum size or next smallest size, the attack deals medium damage to the thrown object and the target as if it were a weapon with a level equal to the mech’s tier. For any smaller objects, the weapon deals light damage instead.
The mech can use this ability to grab and throw a creature or moving vehicle within reach, but to do so, the mech must also succeed at a grapple combat maneuver against the creature to be thrown. If the combat maneuver fails, the hurl action fails, but the mech gains a move action (effectively wasting a standard action).
Scan (Move Action): The mech uses its sensor array to study one creature, mech, or object it is observing with a precise sense. Against a creature, this functions as a check to identify a creature, using the mech’s Computers bonus in place of the skill typically used to identify creatures of that type. If the check succeeds, the mech also gains a +1 insight bonus to the next attack it makes against that creature before the end of its next turn.
If the mech scans a mech or object, the mech attempts a Computers check; against an unattended mech or object, the DC is 10, and against a wielded object or piloted mech, the DC equals 10 + the target’s tier or item level. If it succeeds, the mech identifies two of the following pieces of information about the mech or object (operator’s choice): its hardness, maximum Hit Points, resistances (if any), EAC, KAC, number of passengers or operators, Strength DC to break, speed, full speed (vehicle only), systems or auxiliary systems, or weapons. For every 5 by which the Computers check exceeds the DC, the mech identifies one additional piece of information.
Repeated scans reveal little information unless the mech expends additional energy. Each additional attempt to scan a target requires the mech expend 1 PP for each previous time the mech has attempted to scan that target within the last hour.

Taking Damage

Source Tech Revolution pg. 114
A mech typically has a combination of Hit Points (HP) and Shield Points (SP) that collectively represent how much damage it can sustain before taking penalties or ceasing to function altogether. When a mech takes damage, the damage is first applied to its Shield Points. If its SP are reduced to 0, its shields become inactive until the beginning of the mech’s next turn; for any excess damage, reduce the damage by the mech’s hardness (if any) and apply the remaining damage to the mech’s Hit Points.
At the start of its turn, a mech regains a number of Shield Points equal to its tier, though its total can’t exceed the mech’s maximum Shield Points.
If a mech is reduced to 0 Hit Points, it is wrecked. A wrecked mech can’t perform actions, including sustaining its altitude or depth if airborne or underwater; such mechs typically fall or sink, taking damage as normal. A wrecked mech’s operators aren’t necessarily in danger, though a mech wrecked in a precarious location could be perilous. A wrecked mech can be repaired (see Repairing Damage on page 115).
If a mech ever takes damage that exceeds twice its Hit Points, it’s destroyed and can’t be repaired.

System Failure

Source Tech Revolution pg. 114
As a mech takes damage, its various components can malfunction or become outright inoperable. Whenever a mech is reduced to two-thirds its remaining Hit Points, and again when it’s reduced to one-third its remaining Hit Points, it experiences system failure. To determine which component is affected, roll 1d20 and consult the table below.
If the component doesn’t currently have a system failure, it gains the malfunctioning condition. If the component already has the malfunctioning condition, it gains the inoperable condition. These conditions are explained below.
Overcoming System Failure: Although system damage is devastating, a mech can temporarily overcome these setbacks. At the beginning of its turn, a mech can either spend 2 PP to ignore the malfunctioning condition for any one component or spend 4 PP to treat one component’s inoperable condition as malfunctioning.
1–5Upper Limbs
6–10Lower Limbs
14–16Auxiliary System
17–18Power Core

Upper Limbs: A mech with malfunctioning upper limbs takes a –2 penalty to attack rolls with weapons mounted in upper-limb slots, as well as to any combat maneuvers that don’t use a mech weapon. A mech with inoperable upper limbs can’t use weapons mounted in upper-limb slots.
Lower Limbs: A mech with malfunctioning lower limbs halves movement speeds not provided by an auxiliary system, and the mech takes a –2 penalty to attack rolls with weapons mounted in lower limb slots. If the lower limbs become inoperable, these speeds are reduced to 0; if the mech is hovering or flying using any of these speeds, it begins falling. A mech with inoperable lower limbs can’t use weapons mounted in its lower-limb slots.
Frame: A mech with a malfunctioning frame takes a –2 penalty to attack rolls with weapons mounted in frame slots, and the mech halves its hardness, if it has any. A mech with an inoperable frame can’t use weapons mounted in frame slots, and the mech’s hardness is reduced to 0.
Auxiliary System: Whenever a mech with malfunctioning auxiliary systems attempts to activate an auxiliary system, there’s a 25% chance that the auxiliary system doesn’t function and can’t be used until the beginning of the mech’s next turn; any action and PP used to activate the auxiliary system are wasted. Any auxiliary systems that provide a constant benefit have a 25% chance of not functioning for 1 round at the beginning of each turn.
Auxiliary systems with the inoperable condition behave as though they had the malfunctioning condition, with two exceptions. First, the chance of failure increases to 50%. Second, upon gaining the inoperable condition, select one auxiliary system at random; that auxiliary system ceases to function.
Power Core: The rate at which a mech with a malfunctioning power core regains lost Shield Points and Power Points is halved. The rate at which a mech with an inoperable power core regains lost Shield Points and Power Points is reduced to 0.
When a mech’s power core first gains the malfunctioning condition and again when it gains the inoperable condition, the mech loses 1d4 PP.
Cockpit: The cockpit is the control center where the operators reside. Cockpit system failure doesn’t directly impede the mech but instead threatens one or more operators.
When the cockpit gains the malfunctioning condition, half of the operators (rounded up) take bludgeoning damage equal to 1d8 × the mech’s tier; they can attempt a Reflex saving throw to halve the damage (DC = 15 + half the mech’s tier). When the cockpit gains the inoperable condition, each of the operators takes the bludgeoning damage above (Reflex half). In addition, the operators’ controls become unreliable; the first time each turn that an operator uses a full action to pilot the mech, there’s a 50% chance that the mech doesn’t gain an action. Either effect lasts until the beginning of the mech’s next turn.
Tracking System Failure: The mech sheet on page 165 includes a section for tracking a mech’s systems’ conditions.

Repairing Damage

Source Tech Revolution pg. 115
When a mech combat encounter is over, a mech’s operators can repair damage dealt to their mech, provided it hasn’t been destroyed or lost.
Performing repairs requires stopping the mech, exiting, and working on the mech’s exterior. Any number of allies can use the aid another action to assist with the Engineering checks involved in repairing a mech.
You can remove system failure conditions from a mech component by spending 10 minutes working on the mech and succeeding at an Engineering check. The DC depends on the severity of the condition: DC 20 for malfunctioning and DC 25 for inoperable. If you succeed, you remove that component’s system failure condition, and the component can function as normal.
Restoring a mech’s lost Hit Points is fairly difficult and resource-intensive. You can restore a number of Hit Points equal to twice the mech’s tier by spending 1 hour performing repairs, succeeding at an Engineering check (DC = 10 + 1-1/2 times the mech’s tier), and expending 10 UPBs per point of damage to be repaired. If you exceed the check’s DC by 5 or more, you can reduce the repair time by half or the UPB cost by half. If you exceed the check’s DC by 10 or more, you instead reduce the time and cost by half. If you fail the check by 4 or less, you choose either to make no progress or to increase the UPB cost per Hit Point by 5 for that hour’s repairs. If you fail by 5 or more, you make no progress.
Shield Points regenerate out of combat automatically at a rate of 2 per hour.