| Name | CR | Type | Environment |
| Pahtra, Pahtra Inquisitive | 2 | humanoid (pahtra) | any (Vesk-6) |
| Pahtra, Pahtra Stalker | 6 | humanoid (pahtra) | any (Vesk-6) |
| Pale Stranger | 11 | undead | any |
| Paraforan | 12 | outsider (extraplanar) | vacuum (the Drift) |
| Paraforan, Paraforan Fragment | 6 | outsider (extraplanar) | vacuum (the Drift) |
| Paralith | 4 | aberration | any forests or jungles |
| Phentomite | 1/2 | humanoid (phentomite) | any (Orry) |
| Phentomite, Phentomite Bridger | 6 | humanoid (phentomite) | any (Orry) |
| Philosopher Worm | 7 | monstrous humanoid | any (Nchak) |
| Philosopher Worm, Philosopher Worm Teleologarch | 16 | monstrous humanoid | any (Nchak) |
| Plague Ooze | 7 | ooze | any (Aucturn) |
| Planar Scion, Ifrit | 1/2 | outsider (native) | any |
| Planar Scion, Aasimar | 1 | outsider (native) | any |
| Planar Scion, Oread | 1 | outsider (native) | any |
| Planar Scion, Suli | 1 | outsider (native) | any |
| Planar Scion, Sylph | 2 | outsider (native) | any |
| Planar Scion, Tiefling | 2 | outsider (native) | any |
| Planar Scion, Undine | 1 | outsider (native) | any |
| Planashar | 17 | construct (magical, technological) | any |
| Plasma Ooze | 16 | ooze | any solar or vacuum |
| Plasmalisk | 14 | magical beast | any warm or temperate land |
| Polygulp | 5 | aberration | any aquatic underground |
| Polyphonic Gel | 1/2 | ooze | any land |
| Polyphonic Gel, Polyphonic Plasm | 4 | ooze | any land |
| Predator, Colossal Predator | 13 | animal | any |
| Predator, Gargantuan Predator | 10 | animal | any |
| Predator, Huge Predator | 7 | animal | any |
| Predator, Large Predator | 4 | animal | any |
| Predator, Medium Predator | 1 | animal | any |
| Predator, Predator Swarm | 2 | animal (swarm) | any |
| Predator, Small Predator | 1/3 | animal | any |
| Proog | 1/2 | ooze | any |
| Protean, Durgastr | 16 | outsider (chaotic, extraplanar, protean, | any (Maelstrom) |
| Protean, Rifti | 1 | outsider (chaotic, extraplanar, protean, shapechanger) | any (Maelstrom) |
| Protean, Xiritix | 11 | outsider (chaotic, extraplanar, protean, shapechanger) | any (Drift or Maelstrom) |
| Protocite Reclaimer | 3 | construct (technological) | any (Noma) |
| Protocite Speaker | 2 | construct (technological) | any urban (Noma) |
| Psacynoid, Custodian | 3 | monstrous humanoid | any (Nolasa) |
| Psacynoid, Gallant | 9 | monstrous humanoid | any (Nolasa) |
| Psychic Abomination | 11 | aberration (incorporeal) | any |
| Psychopomp, Erabryth | 1 | outsider (psychopomp) | any (Boneyard) |
| Psychopomp, Morrigna | 11 | outsider (psychopomp) | any (Boneyard) |
| Psydrake | 6 | dragon | any |
| Pyric Harbinger | 8 | aberration | any |
| Pyric Heliacus | 10 | undead | any |
| Pyric Revenant | 4 | undead | any |
| Pyric Wraith | 6 | undead (incorporeal) | any |