| Name | CR | Type | Environment |
| Faceless Hulk (Ugoroth) | 9 | aberration (shapechanger) | any hills or mountains |
| Faceless Stalker | 4 | aberration (shapechanger) | any swamps or underground |
| Faceless Whale | 15 | magical beast | any water |
| Fachen | 5 | aberration | temperate hills or plains |
| Fading Fox | 2 | animal | any temperate land |
| Faerie Mount | 1 | animal | temperate forests, hills, or plains (First World) |
| Fafnheir | 24 | dragon | any (Grungir Forest) |
| Failed Prophet | 11 | construct (augmented humanoid) | any underground or urban |
| Fallen | 8 | undead (incorporeal) | any |
| Familiar, Archaeopteryx | 1/4 | animal | temperate or warm forests |
| Familiar, Arctic Hare | 1/6 | animal | cold forests and plains |
| Familiar, Arctic Tern | 1/6 | animal | cold coastlines |
| Familiar, Armadillo | 1/4 | animal | temperate or warm plains |
| Familiar, Bat | 1/8 | animal | temperate and hot forests and deserts |
| Familiar, Blue-Ringed Octopus | 1/2 | animal (aquatic) | temperate or cold aquatic |
| Familiar, Butterfly/Moth | - | vermin | any temperate or warm |
| Familiar, Cat | 1/4 | animal | temperate and hot plains or urban |
| Familiar, Chicken | 1/6 | animal | any temperate |
| Familiar, Cockroach | 1/8 | vermin | any |
| Familiar, Creeper Ivy | 1/4 | plant | temperate forests and urban |
| Familiar, Dodo | 1/4 | animal | warm coastlines and plains |
| Familiar, Donkey Rat | 1/4 | animal | temperate coast or forest |
| Familiar, Dwarf Caiman | 1/3 | animal | warm swamps and rivers |
| Familiar, Dweomer Cap | 1/8 | plant | any underground |
| Familiar, Fire Salamander | 1/3 | animal | temperate forests |
| Familiar, Flowering Lattice | 1/6 | plant | temperate or warm hills |
| Familiar, Flying Fox | 1/3 | animal | warm forests |
| Familiar, Flying Squirrel | 1/3 | animal | temperate forests |
| Familiar, Fox | 1/4 | animal | any |
| Familiar, Giant Isopod | 1/8 | vermin (aquatic) | any ocean |
| Familiar, Giant Tardigrade | 1/8 | vermin (aquatic) | any |
| Familiar, Goat | 1/3 | animal | any |
| Familiar, Hawk | 1/3 | animal | temperate forests |
| Familiar, Hedgehog | 1/8 | animal | tropical or temperate forests |
| Familiar, Horned Lizard | 1/6 | animal | warm desert |
| Familiar, House Centipede | 1/8 | vermin | temperate or warm forest or underground |
| Familiar, Ioun Wyrd | 1/3 | construct | any |
| Familiar, Jerboa | 1/6 | animal | warm deserts |
| Familiar, Kakapo | 1/8 | animal | warm jungles |
| Familiar, King Crab | 1/4 | vermin (aquatic) | any aquatic |
| Familiar, Koala | 1/4 | animal | temperate and warm forests |
| Familiar, Lamprey | 1/3 | animal (aquatic) | temperate oceans |
| Familiar, Lemming | 1/8 | animal | cold plains |
| Familiar, Leopard Slug | - | vermin | temperate forests |
| Familiar, Lizard | 1/6 | animal | any temperate or warm |
| Familiar, Margay Cat | 1/4 | animal | warm forests |
| Familiar, Meerkat | 1/4 | animal | warm plains |
| Familiar, Mole (FF) | 1/6 | animal | any land |
| Familiar, Mole (UW) | 1/8 | animal | any land |
| Familiar, Monkey | 1/4 | animal | warm forests |
| Familiar, Otter | 1/4 | animal | any water |
| Familiar, Owl | 1/3 | animal | temperate forests |
| Familiar, Peacock | 1/4 | animal | — |
| Familiar, Peafowl | 1/4 | animal | temperate or warm forests |
| Familiar, Penguin | 1/3 | animal | cold plains |
| Familiar, Petrifern | 1/6 | plant | any forest |
| Familiar, Pig | 1/3 | animal | any |
| Familiar, Platypus | 1/6 | animal | temperate or tropical rivers |
| Familiar, Popoto Dolphin | 1/3 | animal | temperate oceans |
| Familiar, Ptarmigan | 1/6 | animal | cold forests and plains |
| Familiar, Pufferfish | 1/4 | animal | warm oceans |
| Familiar, Puffin | 1/8 | animal | cold coastlines |
| Familiar, Rabbit | 1/6 | animal | temperate plains |
| Familiar, Raccoon | 1/2 | animal | temperate forests |
| Familiar, Rat | 1/4 | animal | any temperate |
| Familiar, Raven | 1/6 | animal | any temperate |
| Familiar, Ravenous Tumbleweed | 1/3 | plant | warm deserts or plains |
| Familiar, Razor Fern | 1/4 | plant | temperate forests |
| Familiar, Red Panda | 1/2 | animal | temperate forests or mountains |
| Familiar, Rhamphorhynchus | 1/3 | animal | warm coastlines or forests |
| Familiar, Sawleg Locust | 1/4 | vermin | any desert or plains |
| Familiar, Scarlet Spider | 1/4 | vermin | any |
| Familiar, Seal | 1/3 | animal | any oceans |
| Familiar, Shimmerwing Dragonfly | 1/4 | vermin | temperate or warm swamps |
| Familiar, Sloth | 1/6 | animal | warm forests |
| Familiar, Spiny Starfish | 1/6 | vermin | any ocean |
| Familiar, Squirrel | 1/8 | animal | temperate forests |
| Familiar, Suture Vine | 1/3 | plant | temperate forests |
| Familiar, Tarsier | 1/6 | animal | temperate or warm forests |
| Familiar, Thrush | 1/3 | animal | temperate forests |
| Familiar, Toad | 1/8 | animal | temperate and warm forests |
| Familiar, Trilobite | 1/4 | vermin (aquatic) | any oceans |
| Familiar, Tuatara | 1/4 | animal | temperate islands |
| Familiar, Vampire Squid | 1/2 | animal | any oceans |
| Familiar, Viper | 1/2 | animal | any temperate and warm |
| Familiar, Wallaby | 1/3 | animal | temperate or warm forests |
| Familiar, Weasel | 1/2 | animal | temperate hills |
| Fantionette | 4 | outsider (chaotic, evil, extraplanar) | any (Abyss or Axis) |
| Fastachee | 11 | fey | any temperate land |
| Faun | 1 | fey | temperate forests |
| Fear Eater | 5 | fey | any underground |
| Feargaunt | 9 | outsider (extraplanar, incorporeal) | any (Dimension of Dreams) |
| Feeder in the Depths | 8 | magical beast | any oceans |
| Fell Flotsam | 6 | undead | tropical marshes |
| Fellsig | 3 | undead (fire) | any mountains or underground |
| Fen Mauler | 10 | monstrous humanoid | temperate swamps |
| Feranth | 14 | magical beast | warm deserts or mountains |
| Festering Spirit | 8 | undead (incorporeal) | any land or underground |
| Festrog | 1 | undead | any land |
| Fetchling | 1/2 | outsider (native) | any (Plane of Shadow) |
| Fext | 10 | undead | any |
| Fey Animal | 3 | fey (augmented animal) | cold forests |
| Fey Creature, Fey Giant Toad | 3 | fey | temperate forests, plains, or swamps |
| Fiend-Bred Animal, Chelish Hell-Bred Dog | 2 | animal | temperate or warm forests or plains |
| Fiend-Bred Animal, Quillcat | 1 | animal | any forest |
| Fiend-Bred Animal, Stygian Hot-Blooded Horse | 2 | animal | temperate or warm plains |
| Firbolg | 4 | humanoid (giant) | temperate hills or forests |
| Fire Whale | 16 | magical beast (extraplanar) | any (Plane of Fire) |
| Fish, Dunkleosteus | 6 | animal (aquatic) | any oceans |
| Fish, Giant Blowfish | 5 | animal (aquatic) | warm oceans |
| Fish, Swordfish | 2 | animal (aquatic) | any ocean |
| Fish, Tiger Fish | 1 | animal (aquatic) | warm rivers or swamps |
| Fish, Varisian Hagfish | 1 | animal (aquatic) | temperate water |
| Flail Snail | 4 | magical beast | underground |
| Flea, Giant Flea | 1/2 | vermin | any land or underground |
| Flea, Mammoth Flea | 2 | vermin | temperate forests, hills, mountains, or plains |
| Fleshdreg | 1 | aberration | any ruins |
| Fleshdreg Swarm | 2 | aberration (swarm) | any ruins |
| Fleshwarp, Drider | 7 | aberration | any underground |
| Fleshwarp, Ghonhatine | 10 | aberration | any underground |
| Fleshwarp, Grothlut | 3 | aberration | any underground |
| Fleshwarp, Halsora | 7 | aberration | any underground |
| Fleshwarp, Irnakurse | 9 | aberration | any underground |
| Fleshwarp, Oronci | 5 | aberration | any underground (Darklands) |
| Floodslain Creature, Floodslain Arsinoitherium | 8 | undead (augmented animal) | any plains |
| Floodslain Creature, Floodslain Orc | 3 | undead (augmented humanoid) | any plains or ruins |
| Flotsam Terror | 4 | undead | any ocean |
| Flumph | 1 | aberration | any land or underground |
| Fluxwraith | 17 | undead (incorporeal) | any |
| Flying Polyp | 14 | aberration (air) | any |
| Foo Creature, Foo Dog | 2 | outsider (augmented animal, good, extraplanar) | any (Nirvana) |
| Foo Creature, Foo Lion | 4 | outsider (augmented animal, good, extraplanar) | any (Nirvana) |
| Forge Spurned | 5 | undead (fire) | — |
| Forgefiend (Scanderig) | 10 | outsider (earth, extraplanar)
| any underground (Plane
of Earth)
|
| Forlarren | 2 | fey | temperate plains or forests |
| Formian, Formian Myrmarch | 10 | monstrous humanoid | warm or temperate land or underground |
| Formian, Formian Queen | 17 | monstrous humanoid | warm or temperate land or underground |
| Formian, Formian Taskmaster | 7 | monstrous humanoid | warm or temperate land or underground |
| Formian, Formian Warrior | 3 | monstrous humanoid | warm or temperate land or underground |
| Formian, Formian Worker | 1/2 | monstrous humanoid | warm or temperate land or underground |
| Formless Spawn | 10 | ooze | temperate ruins |
| Forsaken Legion, Forsaken Arbalester | 3 | undead | any ruins (Cheliax or Rahadoum) |
| Forsaken Legion, Forsaken Defender | 4 | undead | any ruins (Cheliax or Rahadoum) |
| Forsaken Legion, Forsaken Foot Soldier | 2 | undead | any ruins (Cheliax or Rahadoum) |
| Fossegrim | 4 | fey (aquatic) | cold or temperate water (waterfalls) |
| Freezing Flow | 4 | ooze (cold, water) | any cold |
| Frightful Haunter | 8 | undead (incorporeal) | any |
| Frog, Frog Father | 5 | animal | warm marshes or water |
| Frog, Giant Frog | 1 | animal | temperate or warm marshes and aquatic |
| Frog, Goliath Frog | 3 | animal | warm marshes or water |
| Frog, Poison Frog | 1/2 | animal | warm marshes and aquatic |
| Froghemoth | 13 | aberration | temperate marsh |
| Frost Fir | 1 | plant (cold) | cold and temperate forests |
| Frost Worm | 12 | magical beast (cold) | cold plains or mountains |
| Frostfallen Creature, Frostfallen Mammoth | 10 | undead (cold) | any cold land |
| Frosty Chiseler | 4 | fey (cold) | any cold |
| Fuldrex | 11 | plant | temperate forests or underground |
| Fungal Crawler | 3 | aberration | any underground |
| Fungal Creature, Fungal Nymph | 8 | plant (augmented fey) | any ruins or underground |
| Fungus Queen | 9 | plant (extraplanar) | any underground |
| Furcifer | 13 | magical beast | any forest |