Corrupted Zero

You are a Reploid (a more advanced version of robots that can express human emotions) like the rest of your kind. Neo Arcadia is the last refuge where Reploids serve people, but an energy crisis occurred and the rulers of Neo Arcadia decided to kill off excess Reploids, and dissenting Reploids and scientists Ciel organize resistance. You, along with the resistance base and scientist Ciel, decided to stop the rulers of Neo Arcadia, but the golems turned out to be too strong, killing resistance members one by one. At some point, you and Ciel reach a dead end. You opened the door and ... You see him ... Zero ... the legendary Reploid, about whom legends and myths were composed. Ciel sacrifices cyber elves to awaken Zero from sleep, and when he got up and where his face should have been, there was blackness as if he had no face and he looked darker than originally, although considering that he slept for 100 years, it is obvious that he is so changed. Along the way, Zero constantly limped and his limbs dangled from side to side. Having reached the golem, Zero tried to defeat it, but he couldn’t do it with just one gun and when hope was lost, the soul of X appeared in front of Zero and without saying a word, he simply nodded his sword to Zero and thus Zero defeated the golem.
Ciel: wow, we seemed right, you really are Zero... the legendary reploid.
Zero:............
Ciel:?
Zero: Zero? my name? Zero... I don’t...
Ciel: don’t worry, you were unconscious for a long time, thanks for saving me.

Actually, this isn't the real Zero... it's something like his evil version, but nobody knows why he became like this. It might be connected to Dr. Weil, and that he brainwashed Zero and made him his puppet. Unlike the usual Zero, he's twice as strong and, to some extent, immortal, and can also attack without weapons.