Controller 1

Relations to the Story
Created Controller 2 and is the only one able to access its information until Controller 4 cut off Controller 1's arm in order to gain said access to information.

Controller 1 was the lead controller of Project Kiteboy.

C1 seems to be the only Controller that Controller 5 doesn't have an grudge on.

Character Traits
Appearance: Humanoid with tentacles. Possibly has only one eye. Missing an arm.

He also takes control of Mike whose real name is Daniel Hutchins. In the video reset Mike/Controller 1 has his arm until the end where it disappears and he bleeds out.

Speculation and Theory
May be C4's brother.