Cadmus, Chaotic Tyrant

Flying, Haste
When Cadmus attacks, Sacrifice a non-land permanent. If you do, Discover X where X is it's
mana value. If you cast a spell this way, if it's
mana value is less than the sacrificed permanent'
mana value, Cadmus gets +Y/+Y until the end of
turn where Y is the difference, it can't be blocked
this turn