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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.