Flowey

+3: add a +1/-1 to any creature, then tap it. every time it is tapped, it gains another counter of the same kind that was just put on it.
-X: flowey exiles any target equal to 1/2 the amount of loyalty lost.
-13: all creatures die and flowey becaomes a 10/0 creature with +x+y, where x is the combined power of all creatures in graveyard, while y is defense.