Although no Monster is truly villainous (excepting perhaps the Deviljho), there have been multiple Monsters who have served an antagonistic role at one point or another. Due to this, only Monsters with a clearly and well-established villainous role will be listed.
Notable Antagonistic Monsters
- Lagiacrus: A Leviathan found in the third generation of Monster Hunter. One specific specimen serves as the main antagonist for much of Monster Hunter 3 and Monster Hunter 3 Ultimate's main campaign, and its subspecies as a major antagonist in the next game.
- Ceadeus: A massive, whale-like Elder Dragon who serves as the true main antagonist of Monster Hunter 3/Monster Hunter 3 Ultimate.
- Deviljho: A nomadic, hyper-aggressive Brute Wyvern notable for its voracious and unending appetite.
- Zinogre: An electricity-laced, wolf-like Fanged Wyvern who serves as the main antagonist of Monster Hunter Portable 3rd.
- Dire Miralis: An Elder Dragon with the attributes of a volcano who serves as final boss of the G-Rank campaign in Monster Hunter 3 Ultimate.
- Gore Magala: An unevolved Elder Dragon who serves as the main antagonist of Monster Hunter 4 and Monster Hunter 4 Ultimate's main campaign.
Types of Monsters
- Lynian: Humanoid Monsters, who appear much more intelligent than their beastly kin and are capable of speech. The only known Monsters of this family are the Felynes/Melynxes and the Shakalakas.
- Herbivores: Herbivorous Monsters of usually peaceful nature, although they are vicious if provoked. Notable Herbivores are the Aptonoth and the Kelbi.
- Neopteron: Insectoids who differ from the similar Carapaceons by being able to fly. Notable Neopterons are the Vespoids and their queen, and the Seltas.
- Carapaceons: Crustaceon Monsters who differ from Neopterons by their more prominent carapaces and lack of wings. Notable Carapaceons are the Daimyo Hermitaur and the Shogun Ceanataur.
- Flying Wyverns: The most common breed of Monsters, Flying Wyverns are dragons under the Wyvern family who are usually capable of flight or otherwise have wings. The most notable of these Monsters are the Rathalos and Rathian.
- Piscine Wyverns: Wyverns that are usually distinguished by their fish-like qualities. Notable Piscines are the Plesioth and the Cephadrome.
- Leviathan: Monsters defined by their aquatic traits. Notable Leviathans include the Lagiacrus and the Nibelsnarf.
- Pelagus: One of the more common breeds of Monsters, the Pelagus are known by their mammalian qualities. They have a subfamily of Monsters called Fanged Beasts. Notable Pelagus are the Arzuros, Congalala, and the Blangonga.
- Bird Wyvern: Wyverns that, true to their name, are usually distinguished by bird-like or otherwise theropodian qualities. The most notable Bird Wyverns are the Dromes (including the "Great" Bird Wyverns of the third generation onwards) and the Yian Kut-Ku.
- Temnoceran: A new breed of Monster that seems to be signified by arachnid-like qualities. The only Monster in this group is the Nerscylla and its subspecies.
- Amphibian: Amphibian Monsters who can dwell both inside water and outside. The only Monsters in this grouping are the Zamtrios and the Zamites, the Tetsucabra, and their respective subspecies.
- Fanged Wyvern: A newly-discovered class of Monster apparently signified by more mammalian qualities without breaching into the Pelagus grouping. The only Monsters in this grouping is the Zinogre and its subspecies.
- Snake Wyverns: Serpentine Wyverns distinguished by their snake-like qualities. Currently, the only Monsters found in this category are the Remobras and the Najarala and its subspecies.
- Brute Wyverns: Bipedal, terrestial Wyverns usually qualified by their brutish, physical nature and their dinosaurian qualities. Notable Brute Wyverns are the Brachydios and the Deviljho.
- Elder Dragon: The most powerful kind of Monsters. These creatures vary wildly in power and form, and never generally fit into any of the other groupings, but the one thing consistent about them is their power. Notable Elder Dragons are the Fatalis brethern, Kushala Daora, Ceadeus, and the Alatreon.