

The Deep Sea King of the Seafolk takes on a dry form when out of the sea for too long, but will return to his hydrated form with enough water. Mosquito Girl is able to undergo a Metamorphosis (変身, Henshin) upon obtaining enough blood and Carnage Kabuto can undergo a transformation into Carnage Mode (阿修羅モード, Ashura Mōdo). Several of the House of Evolution's mutants possess unique transformation abilities.

Though upon regaining their identities and being released from the brainwashing, their monsterization features soon go away as Bang theorizes unlike most Mysterious Beings, the captured humans hearts weren't obsessed and thus they cannot be considered true monsters. It is also possible for someone to become a half-monster through brainwashing such as humans who had been captured by and forced under Do-S' command. Puri-Puri Prisoner refers to his " Angel Style" as a transformation, as he significantly increases his muscle mass, a side effect of which his clothes get torn off. Only Surprise-Attack Plum, Gale Wind, Hellfire Flame and Haragiri are known to have this ability. Some Mysterious Beings that have high willpower possess the ability to transform back and forth between monster and human forms, although in some cases this requires a great deal of training, as seen with the ninjutsu training Gale Wind and Hellfire Flame went through. Several Mysterious Beings possess the ability to transform morphing into an alternate, more powerful form. For example: Marugori through Biceps Brachii King. Through science a human can transform into a monster.A human can become a monster by willingly eating raw Monster Cells.For example: A murder of crows after consuming Beast King's remains. Animals can turn into monsters by consuming the remains of one.

