Prototype K-01-UT

A horrific aberration created by Kojima.

Undertaker Alterna
The first official Prototype Kojima started working on.

Season 4
Kojima couldn't quite capture the Undertaker, so he tried to bring in one from another dimension. The results weren't quite what he was expecting, as he couldn't quite rewrite other universes, this is the best he could bring, a being who exists between the two, with some of his body left in the other reality.

Even then Kojima couldn't get him to cooperate, so he messed with his head and replaced it, turning it into what we see today. This chaotic beast now lacks free will and will only follow Kojima, using him as a monster of destruction with his deadly pure strikes which are delivered with all the force from another dimension.

However, the only thing this being yearns for is release from the suffering.

Episode 9
During the War of the Prototypes, this unit defeated Calypso and netted the first victory for Kojima, but not even this eased his pain.

Episode 10
However, it lost against James Sunderland from TCR due to his experience with horror creatures.

Season 5
It is believed eventually reality could no longer support PURestrikER, and he just collapsed into dust and vanished one day, free from the suffering at last.

Trivia

 * What the fuck Kojima.