(The SkyWalker Comics mythos)
Biohazard 0 VOL.5 - pages 16 and 17

The Zombie King's introduction in biohazard 0 VOL.5.

The Zombie King was a winged mutant sealed within a coffin in the death castle. He appears in biohazard 0.

Further notes

The Zombie King is based on the "Crimson Head Prototype 1", a boss in the 2002 Resident Evil remake.