Mercury

"..he was once our brother, now he calls himself Mercury - it is no secret now that his encounter with Adam Man left more than just scars on his body.. it had infected him with Adam's nanites.. we all knew Mercury was no longer a Ship-Mouse but rather an extension of Adam Man, the being that had tried to massacre us.. we also know that the day shall come when we will have to fight him - for now we keep him.. clinging to a small hope that perhaps somehow.. some way.. our brother will return to us..". ~ Jacob's Ladder

Mercury is a major antagonist in the Ship-Mice series, which will act as the prequel of At Err, explaining how the Ship-Mice that survived the events of SIM - Termination escaped Earth alongside several allies and colonized parts of At Err, which resulted in rogue ISDF agents invading At Err under the command of General Milton in the future.