Liliana's Shield Maiden

Defender
Zombies you control get a +1/+1 and islandwalk
Creatures can't attack you unless their controller
pays {x}, where X is the number of zombies in
your graveyard. During your upkeep, sacrifice two creatures, if you can't each opponents gain X life
equal to this creature power.
Liliana's Shield Maiden get a +0/+X, where X is
the number of zombies you control