Obsessive Slaughterer (Side 1)

—Obsessive Murderer enters the battlefield
with a number of -1/-1 counters equal to
half the amount of life spent to cast it.
—Whenever another non-token non-artifact
creature you control dies, create a token
that's a copy of it except its a 5/5 artifact
with decayed in addition to its other types.
—When Obsessive Murderer dies, exile it,
then return it to the battlefield transformed
under your control.