Sera is the Mother Unit in charge of the systems on Elysium. Sera is trapped in a large, floating stasis field until MegaMan visits Forbidden Island and unintentionally releases her.

She and Geetz convince Von Bluecher and Barrell that to unlock the Mother Lode they must obtain the Four Keys. Eventually it turns out that Sera has plans for the Keys, and will face Trigger in battle before the end.

Sera appears quiet, serious, and rather lifeless, though there is an emotional stir within her unseen in her logical talk and actions.