Zero is a character who appears in Deadlock.
He only appears towards the end of the book but plays a crucial part.
Zero is one of the numerous clones of Otto who were designed to be more powerful, stronger and faster than he is. He was one of the prototypes but unlike Otto he is more of a machine than a human and was grown at an accelerated rate like the other clones who only make an appearance in an epilogue at the end of the book.
Zero is capable of using the electronic impulses running through a person's nervous system to control their bodies but is later killed by Otto, who was using that exact power against him. Otto then impersonates him leading his friends to believe, for a short period of time, that he is dead.