| Name | CR | Type | Environment |
| Kalo, Kalo Deepspeaker | 5 | monstrous humanoid (aquatic) | any aquatic (Kalo-Mahoi) |
| Kalo, Kalo Sharkhunter | 2 | monstrous humanoid (aquatic) | any aquatic (Kalo-Mahoi) |
| Kaukariki | 1 | magical beast | warm forests (Castrovel) |
| Kayal | 7 | outsider (native) | any (Shadow Plane) |
| Khefak | 1/3 | vermin | any (Akiton) |
| Khefak, Thasteron Khefak | 3 | vermin | any (Akiton) |
| Kish | 4 | humanoid (kish) | any (Nejeor VI) |
| Ksarik | 4 | plant | temperate or warm forests (Castrovel) |
| Kurobozu | 9 | undead | any |
| Kyokor | 20 | magical beast (colossus) | any (Daimalko) |