According to Damian Tryp, Homo Killcrop is a genetic predecessor to Homo superior. Also known as Changelings, Killcrops or Replacement People, this category of mutants possesses an X-Gene which manifests at birth instead of during adolescence. The evolutionary trait of delaying the onset of mutant powers helped more members of the species survive and proliferate.[1]

In centuries past most were murdered in infancy or even abandoned at birth. The remainder became scapegoats for poor harvests[1] and plagues.[2]

Eventually, the "change", the mutation was "buried until adolescence", ensuring the survival of the mutants, and leading to Homo superior.[1]

Changelings are still considered by most to be merely a subset of mutants, since several mutants in the modern era have manifested either all or part of their abilities at birth, but Damian Tryp presented changelings as a separate species. Seeing as how his motives were to convince Jamie Madrox's parents of his own personal ability to take care of their son as opposed to Professor X, he may have been disingenuous as to how large the differences between changelings and mutants are.[1]

It is still unknown for Steve Rogers if the killcrop is a separate genus of mutants, or a mutant subtype.[3]

Madrox was deemed to be a genetic throwback.[1]

Powers and Abilities





Average Strength level





Habitat: Earth
Gravity: 9.80665 m/s²
Atmosphere: Roughly 78.09% Nitrogen, 20.95% Oxygen, 0.93% Argon, 0.038% Carbon Dioxide, and small amounts of other gases.
Population: Two (Madrox and Damian Tryp).


Level of Technology: Identical to their era's technology.
Representatives: Allegedly Madrox and Damian Tryp.

Mutants activated at birth or Homo Killcrops

Quote1 'Henry McCoy is one those rare mutants whose mutations [...] were apparent at the earliest stages of his childhood.' Quote2
--X-Men Declassified #1

Many mutants have used their powers before their puberty, without a clear statement and the use of one of the terms for that (sub)species.

Tryp sort of stated that mutants didn't reveal themselves at birth, and opposed to the idea of exceptions,[1] making all the early activated mutants changelings in his perspective.


They were named Killcrops because they were blamed for poor harvests, and later "Homo Killcrop" by Damian Tryp, as "Killcrops" was his "favorite" name for his kind.[1]

See Also

Links and References


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