Mutation is a game system where monsters change into new variants due to environmental and ecosystem conditions. When you restore an area, the ecosystem evolves, and you get mutated versions of monsters. Monsters can gain new elements when eggs inherit the region’s element in Monster Hunter Stories 3. The new abilities and expanded skill pools make them stronger and more flexible in combat. Raising ecosystem rank and hatching mutated eggs let you mutate the monsters.
What Are Mutated Monsties
Mutations in Monster Hunter Stories 3 are core mechanics where the monsters change into new forms depending on their base environment. The ecosystem evolves when you restore a habitat by hatching the egg. Mutated monsties are new variants of regular monsters that come with new elements, gens, skills, and abilities.
These type of monsters changes their appearance and become rare variants. The mutation of Mutated monsties depends on the region and habitat conditions. A monster may change elements if placed in a different ecosystem. Eggs found in restored habitats can hatch into dual-element monsties, allowing them to gain a secondary element. For example, a thunder monster becomes a Fire + Thunder type of beast.
How Mutation Works
Mutated monsties often have different designs and colors from the normal ones. They get new skill pools, genes, and better element coverage in Monster Hunter Stories 3. Mutation can also create Subspecies, Deviants, and rare monsters unlocked when the specific conditions are met.
The mutation happens when you hatch monsties and release them into a region. After that, the ecosystem increases, and you increase the Rank for mutated eggs and hatch eggs at the end to get mutated monsties. Some mutations require the presence of specific monsters in the habitat and certain ranks.
All Mutated Monsties
Below are all the Mutated Monsties along with their rank, category, and element in Monster Hunter Stories 3.
| Monster | Category | Rank | Element | Abilities | How To Get |
| Pink Rathian | Flying Wyvern | 5 | Fire | Fly, Jump, Melee Attack, Roar, Breath | Increase the ecosystem rank of Rathian to B using Habitat Restoration. |
| Dreadqueen Rathian | Flying Wyvern | 7 | Fire | Fly, Jump, Melee Attack, Roar, Breath | Force the Invasive Yian Garuga to retreat. Restore it in a habitat that includes 3 or more poisonous monsters. Get more Rathians and release them into the habitat to Rank S. |
| Ivory Lagiacrus | Leviathan | 6 | Thunder | Swim, Jump, Roar, Melee Attack, Breath | Increase the ecosystem rank of Lagiacrus to A by using Habitat Restoration. |
| Boltreaver Astalos | Flying Wyvern | 7 | Thunder | Fly, Jump, Roar, Melee Attack, Breath | Force the Invasive Seregios to retreat and get Astalos. Restore it in a habitat that includes 3 or more lightning monsters. Get more Astalos and release them into the habitat to reach Rank S. |
| Deadeye Yian Garuga | Bird Wyvern | 7 | Fire | Fly, Jump, Melee Attack, Roar, Breath | Get the Yian Garuga from an egg after forcing the Invasive Yian Garuga to retreat. Restore it in a habitat with the presence of 3 or more Monsters ranked 5-Star. Get more Yian Garuga and release them into the habitat to reach Rank S. |
| Green Nargacuga | Flying Wyvern | 5 | Non-Elemental | Jump, Wall Climb, Stealth, Melee Attack | Use Habitat Restoration to increase the ecosystem rank of Nargacuga to A. |
| Silverwind Nargacuga | Flying Wyvern | 7 | Non-Elemental | Jump, Melee Attack, Wall Climb, Stealth | Force the Invasive Nerscylla to retreat by attacking its weak point and get the Nargacuga from the dens inside. Restore it in a habitat that includes 3 or more wind-focused monsters. Obtain more Nargacuga and release them into the habitat until you reach Rank S. |
| Soulseer Mizutsune | Leviathan | 7 | Water | Swim, Jump, Roar, Melee Attack, Breath | Get the Mizutsune from an egg from the dens after forcing the Invasive Shogun Ceanataur to retreat. After that, restore it in a habitat that includes Zinogre as well. Get more Mizutsune and Zinogres, and release them into the habitat until you reach Rank S. |
| Brute Tigrex | Flying Wyvern | 6 | Non-Elemental | Wall Climb, Jump, Roar, Melee Attack | Increase the ecosystem rank of Tigrex to A. |
| Grimclaw Tigrex | Flying Wyvern | 7 | Non-Elemental | Wall Climb, Jump, Roar, Melee Attack | Use Habitat Restoration to increase the ecosystem rank of 4 Power Monsters to S. |
| Bloodbath Diablos | Flying Wyvern | 7 | Non-Elemental | Jump, Roar, Melee Attack, Ground Dive | Use Habitat Restoration to boost the ecosystem rank of Diablos to S in Tarkuan’s Bountiful Dunes. |
| Hellblade Glavenus | Brute Wyvern | 7 | Fire | Jump, Roar, Melee Attack, Breath | Increase the ecosystem rank of Glavenus to S by Habitat Restoration. |
| Stygian Zinogre | Fanged Wyvern | 6 | Dragon | Wall Climb, Jump, Roar, Melee Attack | Increase the ecosystem rank of Zinogre to A by using Habitat Restoration. |
| Thunderlord Zinogre | Fanged Wyvern | 7 | Thunder | Wall Climb, Jump, Roar, Melee Attack | Rank up Zinogre or Stygian Zinogre to Ecosystem Rank S. |
| Sand Barioth | Flying Wyvern | 5 | Non-Elemental | Fly, Jump, Wall Climb, Roar, Melee Attack, Breath | Enhance the ecosystem rank of Barioth to A using Habitat Restoration. |
| Azure Rathalos | Flying Wyvern | 6 | Fire | Fly, Jump, Roar, Melee Attack, Breath | Use Habitat Restoration to increase the ecosystem rank of Rathalos to A. |
| Dreadking Rathalos | Flying Wyvern | 7 | Fire | Fly, Jump, Roar, Melee Attack, Breath | Boost the ecosystem rank of Rathalos to S in a habitat with the presence of 4 or more Flying Wyvern monsters. |
Mutated Monsties can fight alongside you in battles like any Monstie and can be added to your party in Monster Hunter Stories 3. They can use skills, Kinship Skills, and abilities, allowing you to win every fight against high-level enemies. You don’t mutate an existing Monstie directly, but you farm eggs, raise ecosystem rank, and hatch a new mutated version.
I recommend not going for a Mutation Trigger fight without learning the weakness beforehand. They often have better combat flexibility and synergy with the normal ones. Subspecies or deviant variants are also very powerful, making mutated monsties essential for progression.
