Nightblood

Indestructible
Nightblood can neither attack nor block
Destroy Evil {3}{p/w}{p/b}{t} (destroy target permanent)
Bestow {3}{p/w}{p/b} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Enchanted creature gains 'Destroy Evil' and Devour Soul {6}{p/c}{p/c}{p/c} (Pay half your life total and target player loses the game)