The Grimm are monsters inhabiting the world of Remnant that are fought by Huntsmen and Huntresses, such as those trained at Beacon Academy. All Grimm have similarities to ordinary animals, but are pitch-black with red-and-white bone-like plates and spikes on their bodies.
- Creeps, a small reptile or dinosaur-like creature with tails and two legs, but no forelimbs.
- Alpha Creeps, a larger, more dangerous version of Creeps with more armour and bigger spikes.
- Mutant Creeps, a mutated version of the Creep, more reminiscent of the Alpha Creep in size and appearance, except for the addition of green to its colour scheme, green crystals or spines protruding from it's back, and the green fog it emits.
- Beowolves, a bipedal wolf-like creature, with small spikes down it's back. In RWBY: Grim Eclipse (Fan-Made), the Beowolves are entirely black with red eyes.
- Alpha Beowolves, a larger, more dangerous version of Beowolves, with slightly thicker spines and an external rib cage.
- Mutant Beowolves, a mutated version of the Beowolf, closer to the Alpha Beowolf in size, with a similar colour scheme to the Mutant Creep, with green crystals or spines protruding from it's back.
- Ursa Minor, a massive bear-like creature with facial markings and some spines.
- Ursa Major, an even bigger, bear-like creature, with much bigger spines, and chest plating.
- Boarbatusks, a boar-like creature with large tusks.
- Mini Deathstalkers, a grimm version of scorpions, about the size of creeps, with a gold stinger.
- Mutant Deathstalker, a huge, mutated version of the Mini Deathstalker, with a green colour scheme.