Amuscaria, Ghastly Dragon (ZScript conversion), LazarusGLDefs:
Raven Software, ZDoom WRWSprites:
Raven Software, id SoftwareSprite Edit:
Hexen Heresiarch, Hellstorm Dark Avatar
The Avatar is meant to be used as a mini-boss. It has several attacks; a stream of fireballs; a large globe of energy that continually fragments into smaller orbs on contact; a large, homing projectile; and a wave of lightning. It's best placed in areas that have just enough cover to defend against its attacks, and it has enough health to last a while.