| Name | CR | Type | Environment |
| Wakandagi | 14 | outsider (native, water) | temperate rivers |
| Walcofinde | 2 | undead | any underground |
| Waldgeist | 8 | undead (incorporeal) | any forests |
| Walrus, Emperor Walrus | 8 | animal | cold oceans |
| Walrus, Walrus (B4) | 3 | animal | cold oceans |
| Walrus, Walrus (FF) | 4 | animal | cold coastlines |
| Wamp | 6 | aberration | any (ruins or graveyards) |
| War Beast of Belkzen, Bull of Zagresh | 7 | animal | any hills or plains |
| War Beast of Belkzen, Warcat of Rull | 13 | animal | cold hills or mountains |
| Warden Jack Swarm | 4 | construct (swarm) | — |
| Warmonger | 19 | construct | any |
| Warmonger Wasp | 7 | construct (extraplanar) | any (Abyss) |
| Warped One | 8 | outsider (chaotic, evil, extraplanar)
| any (Abyss)
|
| Warpglass Ooze | 2 | ooze | any |
| Warsworn | 16 | undead | any |
| Wasp, Giant Wasp | 3 | vermin | temperate forests |
| Wasp, Ground Wasp Swarm | 2 | vermin (swarm) | warm deserts or plains |
| Wasp, Wasp Swarm | 3 | vermin (swarm) | temperate forests |
| Watcher | 22 | outsider | any (Jandelay) |
| Water Leaper | 2 | magical beast (aquatic) | any lakes or swamps |
| Water Orm | 10 | magical beast (aquatic) | any lakes |
| Water Strider Swarm | 1 | vermin (swarm) | temperate lakes, rivers, or swamps |
| Water Strider, Giant Water Strider | 1 | vermin | any water |
| Water Strider, Nymph Water Strider | 1/4 | vermin | any water |
| Water Wraith | 2 | magical beast (aquatic) | warm rivers (Garund) |
| Waxwork Creature | 2 | construct | any |
| Wayang | 1/2 | humanoid (wayang) | temperate forests |
| Weasel, Dire Weasel | 3 | animal | any land |
| Weasel, Giant Weasel | 1 | animal | any land |
| Weaverworm | 8 | aberration | any forests or hills |
| Weedwhip | 2 | plant | temperate or warm forests |
| Wendigo | 17 | outsider (cold, native) | any cold |
| Whale | 10 | animal | any oceans |
| Whale, Great White Whale | 14 | animal | any oceans |
| Whaler Jellyfish | 17 | vermin (aquatic) | any oceans |
| Whirlmaw | 8 | aberration | warm deserts (Rahadoum) |
| Whisperer | 20 | fey (extraplanar, incorporeal) | any wilderness |
| Whyrlish | 15 | aberration (extraplanar) | any air (Astral Plane) |
| Wickerman | 13 | construct (fire) | any land |
| Wight | 3 | undead | any |
| Wikkawak | 4 | humanoid (goblinoid) | cold mountains |
| Wild Hunt, Wild Hunt Archer | 13 | fey (wild hunt) | any land |
| Wild Hunt, Wild Hunt Horse | 11 | fey (wild hunt) | any land |
| Wild Hunt, Wild Hunt Hound | 10 | fey (wild hunt) | any land |
| Wild Hunt, Wild Hunt Monarch | 19 | fey (wild hunt) | any land |
| Wild Hunt, Wild Hunt Scout | 15 | fey (wild hunt) | any land |
| Will-o’-Wisp | 6 | aberration (air) | any swamp |
| Wings of Protection | 8 | construct | Dragonfall |
| Winter Fey (Redcap) | 7 | fey (cold) | temperate forests, mountains, or underground |
| Winterwight | 17 | undead (cold) | any cold land |
| Wisagatcak | 14 | outsider (evil, extraplanar, lawful) | cold mountains (Hell) |
| Witchcrow | 3 | magical beast | cold or temperate forests or plains |
| Witchcrow | 1 | magical beast | cold and temperate forests and plains |
| Witchcrow, Greater Witchcrow | 3 | magical beast | cold and temperate forests and plains |
| Witchfire | 9 | undead (incorporeal) | any swamps or woodlands |
| Witchwyrd | 6 | monstrous humanoid | any land |
| Wizard's Shackle | 1/2 | aberration (aquatic) | any water |
| Wolf | 1 | animal | cold or temperate forests |
| Wolf, Dire Wolf | 3 | animal | cold or temperate forests |
| Wolf, Timber Wolf | 2 | animal | cold forest or mountains |
| Wolf-in-Sheep's-Clothing | 8 | aberration | any forest |
| Wolliped | 3 | animal | temperate hills |
| Wolliped, Wolliped (Combat Trained) | 3 | animal
| temperate hills
|
| Wolliped, Wolliped (Domesticated or Wild) | 3 | animal
| temperate hills
|
| Wolpertinger | 1 | magical beast | temperate forests or hills |
| Wolverine | 2 | animal | cold forests |
| Wolverine, Dire Wolverine | 4 | animal | cold forests |
| Wooden Protector | 3 | plant | any forest or jungle |
| Worg | 2 | magical beast | temperate forests and plains |
| Worg, Winter Wolf | 5 | magical beast (cold) | cold forests and plains |
| Worm That Walks | 14 | vermin (augmented human) | any |
| Worm That Walks, Locust Variant | 8 | vermin (augmented human) | — |
| Woundwyrm | 15 | dragon (chaotic, evil) | any (the Worldwound) |
| Wrackworm | 20 | outsider (chaotic, evil, extraplanar) | any |
| Wraith | 5 | undead (incorporeal) | any |
| Wraithwing | 4 | undead | temperate mountains |
| Wrathplated Clockwork Mage | 10 | construct (clockwork) | any land |
| Wretchghost | 5 | undead (incorporeal) | any |
| Wyrmwraith | 17 | undead (incorporeal) | any |
| Wyrwood | 1/2 | construct | any ruins or underground |
| Wysp, Aether Wysp | 2 | outsider (aether, elemental) | — |
| Wysp, Air Wysp | 2 | outsider (air, elemental) | — |
| Wysp, Earth Wysp | 2 | outsider (earth, elemental) | — |
| Wysp, Fire Wysp | 2 | outsider (elemental, fire) | — |
| Wysp, Water Wysp | 2 | outsider (elemental, water) | — |
| Wyvaran | 1/2 | dragon | temperate mountains |
| Wyvern | 6 | dragon | temperate or warm hills |