| Name | CR | Type | Environment |
| Damai | 1/2 | humanoid (damai) | any (Daimalko) |
| Damai, Damai Guardian | 12 | humanoid (damai) | any (Daimalko) |
| Deh-Nolo | 14 | aberration | any |
| Demon, Pluprex | 13 | outsider (chaotic, demon, evil, extraplanar) | any (Abyss) |
| Demon, Prexian Mutantspawn | 11 | outsider (chaotic, evil, extraplanar) | any (Abyss) |
| Devil, Endbringer Devil (Dhalochar) | 19 | outsider (devil, evil, extraplanar, lawful) | any (Hell) |
| Devil, Warmonger Devil (Levaloch) | 7 | outsider (devil, evil, extraplanar, lawful) | any (Hell) |
| Dinosaur, Ceratopsid | 8 | animal | any |
| Dinosaur, Dromaeosaurid | 3 | animal | any |
| Dinosaur, Plesiosaur | 7 | animal | any water |
| Dinosaur, Pterosaur | 3 | animal | any |
| Dinosaur, Sauropod | 10 | animal | any |
| Dinosaur, Theropod | 9 | animal | any |
| Dinosaur, Thyreophoran | 6 | animal | any |
| Draelik | 2 | humanoid (draelik) | any (Great Shadar) |
| Dragon (Chromatic), Young Adult Blue Dragon | 11 | dragon (earth) | any |
| Dragon (Metallic), Adult Silver Dragon | 14 | dragon (cold) | any |
| Dragon (Outer), Old Void Dragon | 18 | dragon | any vacuum |
| Dragonkin | 9 | dragon | any (Triaxus) |
| Drake, Radiation Drake | 9 | dragon | any |
| Dreamer | 8 | aberration | any sky (Liavara) |
| Driftdead | 2 | undead (extraplanar) | any (the Drift) |
| Drow, Drow Enforcer | 1 | humanoid (elf) | any (Apostae) |
| Drow, Drow Noble Arms Dealer | 11 | humanoid (elf) | any (Apostae) |
| Dust Manta | 6 | magical beast | warm deserts |
| Dust Manta, Dust Manta Monarch | 12 | magical beast | warm deserts |