Destroyer

The Destroyer is an entity of incredible power, and he is the main villain throughout the 15 Keys universe, seeming not to exist in Fate by Blades.

History
The Destroyer is Zach, but has amplified powers. It is a darker version of him and is obssessed with destroying. The Destroyer is also the only identified being who Cero cant kill in a few seconds.

Trivia
The Destroyer is Mark 1 when first met, however when the dimension collapses he is mark 217.