| Name | CR | Type | Environment |
| Paguroida | 9 | monstrous humanoid (aquatic) | temperate coastlines |
| Pale Stranger | 10 | undead | any |
| Pallid Angel | 12 | outsider (evil, extraplanar) | any (Abaddon) |
| Panda | 2 | animal | temperate or warm jungles |
| Panotti | 2 | humanoid | any land |
| Papinijuwari | 13 | humanoid (giant) | warm plains |
| Pard | 3 | magical beast | temperate or warm forests or plains |
| Pavbagha | 4 | outsider (extraplanar, lawful) | any (Axis) |
| Pech | 3 | fey (earth) | any underground (Plane of Earth) |
| Pegasus | 3 | magical beast | temperate and warm plains |
| Peluda | 10 | dragon | temperate marshes or plains |
| Penanggalen | 5 | undead (augmented humanoid) | any |
| Peri | 14 | outsider (good, native) | any good-aligned plane |
| Peryton | 4 | magical beast | any |
| Pest Drake Swarm | 9 | dragon (swarm) | any urban |
| Petitioner | 1 | outsider (extraplanar) | any (Outer Planes) |
| Petrified Maiden | 6 | undead | any land (Field of Maidens) |
| Petromin | 1/3 | animal | any deserts |
| Peuchen | 10 | magical beast (shapechanger) | any warm or temperate land |
| Phantom Armor, Giant Phantom Armor | 4 | undead | any |
| Phantom Armor, Guardian Phantom Armor | 2 | undead | any |
| Phantom Armor, Hollow Helm | 1 | undead | — |
| Phantom Armor, Phantom Lancer | 6 | undead | — |
| Phantom Fungus | 3 | plant | any underground |
| Pharaonic Guardian | 11 | undead (incorporeal) | warm ruins |
| Pharmakos | 15 | aberration (aquatic) | any |
| Phase Spider | 5 | magical beast | warm hills |
| Phoenix | 15 | magical beast (fire) | warm desert and hills |
| Phoenix, Pyralisia, the Rain of Embers | 18 | magical beast (fire) | — |
| Phycomid | 4 | plant | any underground |
| Pickled Punk | 1 | undead | any |
| Pilo | 2 | animal | any deserts |
| Pipefox | 2 | magical beast | any |
| Piranha Swarm | 3 | animal (aquatic, swarm) | any aquatic |
| Piranha Swarm | 3 | animal (aquatic, swarm) | warm freshwater |
| Piranha Swarm, Megapiranha Swarm | 6 | animal (aquatic, swarm) | any aquatic |
| Pixie | 4 | fey | temperate forests |
| Pixie Circle | 7 | plant | temperate forests and jungles |
| Plagued Beast, Plagued Horse | 2 | undead (augmented animal) | any |
| Plankta | 17 | aberration (aquatic, earth) | any oceans |
| Plasma Ooze | 16 | ooze | any |
| Polevik | 5 | fey | any swamp or underground |
| Polong | 8 | undead (incorporeal) | any |
| Poltergeist | 2 | undead (incorporeal) | any |
| Poludnica | 10 | fey
| temperate plains
|
| Pooka | 2 | fey | any |
| Popobala | 15 | monstrous humanoid (shapechanger) | warm coasts or forests |
| Poppet, Poppet, Small | 1/2 | construct | — |
| Poppet, Poppet, Tiny | 1/3 | construct | — |
| Porcupine | 1/4 | animal | temperate forests or plains |
| Porcupine, Giant Porcupine | 2 | animal | temperate forests or plains |
| Prana Ghost | 11 | outsider (augmented humanoid, elf, extraplanar, human, incorporeal) | any |
| Primeval Sea Creature, Kronosaurus | 10 | animal | warm oceans |
| Primeval Sea Creature, Nothosaur | 5 | animal | any water |
| Primeval Sea Creature, Zeuglodon | 9 | animal | warm oceans |
| Protean, Akizendri | 3 | outsider (chaotic, extraplanar, protean, shapechanger) | any (Maelstrom) |
| Protean, Azuretzi | 5 | outsider (chaotic, extraplanar, protean, shapechanger) | any (Maelstrom) |
| Protean, Hegessik | 15 | outsider (chaotic, extraplanar, protean, shapechanger) | any (Maelstrom) |
| Protean, Ibshaunet | 11 | outsider (chaotic, extraplanar, protean, shapechanger) | any (Maelstrom) |
| Protean, Illureshi | 9 | outsider (chaotic, extraplanar, protean, shapechanger) | any (Maelstrom) |
| Protean, Imentesh | 10 | outsider (chaotic, extraplanar, protean, shapechanger) | any (Limbo) |
| Protean, Izfiitar | 20 | outsider (chaotic, extraplanar, protean,
shapechanger) | any (Maelstrom) |
| Protean, Keketar | 17 | outsider (chaotic, extraplanar, protean, shapechanger) | any (Limbo) |
| Protean, Naunet | 7 | outsider (chaotic, extraplanar, protean, shapechanger) | any (Limbo) |
| Protean, Oshageros | 13 | outsider (chaotic, extraplanar, protean, shapechanger) | any
(Maelstrom) |
| Protean, Ourdivar | 4 | outsider (chaotic, extraplanar, protean, shapechanger) | any (Maelstrom) |
| Protean, Pelagastr | 8 | outsider (chaotic, extraplanar, incorporeal, protean,
shapechanger) | any (Maelstrom) |
| Protean, Voidworm | 2 | outsider (chaotic, extraplanar, protean, shapechanger) | any (Limbo) |
| Proto-Shoggoth | 11 | ooze | any |
| Proto-Shoggoth, Proto-Shoggoth Synctium | 14 | ooze | any |
| Pseudodragon | 1 | dragon | temperate forests |
| Pseudosphinx | 2 | magical beast | warm deserts |
| Pseudowyvern | 2 | dragon | temperate or warm forests or hills |
| Psoglav | 13 | monstrous humanoid | any underground |
| Psyche Serpent | 2 | magical beast | any temperate or warm |
| Psychemental | 8 | outsider (extraplanar, incorporeal) | any (Astral Plane) |
| Psychepore | 7 | plant | warm forests or jungles |
| Psychic Stalker | 7 | undead (incorporeal) | any |
| Psychoplasmic Creature, Psychoplasmic Behir | 9 | outsider (augmented magical beast, extraplanar) | any (Astral Plane) |
| Psychopomp Usher, Barzahk | 28 | outsider (extraplanar, psychopomp, shapechanger) | — |
| Psychopomp, Ahmuuth | 4 | outsider (extraplanar, psychopomp) | any (Boneyard) |
| Psychopomp, Algea | 11 | outsider (extraplanar, psychopomp, swarm) | any (Boneyard) |
| Psychopomp, Calaca | 8 | outsider (extraplanar, psychopomp) | any (the Boneyard) |
| Psychopomp, Catrina | 5 | outsider (extraplanar, psychopomp) | any (Purgatory) |
| Psychopomp, Ember Weaver | 8 | outsider (psychopomp, extraplanar) | any (Astral Plane) |
| Psychopomp, Esobok | 3 | outsider (extraplanar, psychopomp) | any (Boneyard) |
| Psychopomp, Fulgati | 18 | outsider (extraplanar, psychopomp) | any (Boneyard) |
| Psychopomp, Kere | 10 | outsider (psychopomp, extraplanar) | any (graveyards or the Boneyard) |
| Psychopomp, Memitim | 15 | outsider (extraplanar, psychopomp) | any (Boneyard) |
| Psychopomp, Morbai | 6 | outsider (extraplanar, psychopomp) | any (Boneyard) |
| Psychopomp, Morrigna | 13 | outsider (extraplanar, psychopomp) | any (Purgatory) |
| Psychopomp, Nosoi | 2 | outsider (extraplanar, psychopomp) | any (Purgatory) |
| Psychopomp, Olethros | 17 | outsider (extraplanar, psychopomp) | any (Boneyard) |
| Psychopomp, Shoki | 9 | outsider (extraplanar, psychopomp) | any (Boneyard) |
| Psychopomp, Vanth | 7 | outsider (extraplanar, psychopomp) | any (Purgatory) |
| Psychopomp, Viduus | 4 | outsider (extraplanar, psychopomp) | any (Boneyard) |
| Psychopomp, Yamaraj | 20 | outsider (extraplanar, psychopomp) | any (Purgatory) |
| Pukwudgie | 7 | monstrous humanoid (shapechanger) | temperate forests, hills, or mountains |
| Purple Worm | 12 | magical beast | any underground |
| Putrid Ooze | 11 | ooze | any |
| Pyrausta | 1/4 | dragon (fire) | any warm |
| Pyrogeist | 10 | undead (incorporeal) | any |
| Pyropiscis | 8 | magical beast (fire) | warm mountains or underground |