| Name | CR | Type | Environment |
| Maraquoi, Maraquoi Hunter | 1/2 | humanoid (maraquoi) | any (Marata) |
| Maraquoi, Maraquoi Shaman | 8 | humanoid (maraquoi) | any (Marata) |
| Marooned One | 8 | undead | any |
| Marrowblight | 7 | undead | any ruins (Eox) |
| Mohrg | 8 | undead | any |
| Mountain Eel | 6 | animal | temperate or warm mountains (Castrovel) |