here's my idea for a zombie xyz monster

Reborn Ogre
Rank 4/Dark
Zombie/XYZ/Effect
3 Lvl 4 Zombie-Type Monsters
Atk 3000/Def 0

Face-up Zombie-Type monsters you control cannot be destroyed by card effects. Once per turn: You can detach 1 Xyz Material from this card to Special Summon 1 Zombie-Type monster from your hand, deck, or graveyard. This card cannot attack during the turn you activate this effect.