Arellera, Balanced Law

Indestructible
Sacrifice a creature: Add {x} where {x} is the sacrificed creature's converted mana cost.
{x}: Destroy target creature with converted mana
cost {x}
Sacrifice creatures with a combined converted
mana cost of 6 or more: Return Arellera, Balanced
Law to the battlefield from exile.
"I am sorry, but there is no madness to this method."