Metamorphosis, (Japanese: 変身 henshin), is a process in which a Meta Monster transforms into a stronger species after certain conditions are met. Metamorphosis may contain multiple stages, and most Meta Monsters are able to transform twice.
Metamorphosis is spiritually similar to evolution from the Pokemon series in that a Meta Monster undergoes a transformation that changes it into a different creature, while retaining traits from its original form. Most Meta Monsters that can undergo this process will transform after reaching a certain level, much like in Pokemon. However, new methods of transforming have been introduced that are rather different from Pokemon. A few of these include conditions such as leveling up during a certain time of day in real time, filling a rage meter triggered from taking damage in several battles, and catching them in a certain type of Disc Capsule. Whenever a Meta Monster undergoes Metamorphosis, it will be seen transforming into the next trasformation stage, rather than changing through a flash of light.
- Meta Monsters are named after the procedure of metamorphosis, despite the fact that some do not transform.