The Boogeyman

On your upkeep, choose a target creature at
random with converted mana cost 2 or more.
That creature becomes the boogeyman until end
of turn.
(That creature has{t}: This creature fights another
target creature. On your end step, if that creature has
not killed another creature with converted mana cost 2 or
more , that creature's base power and toughness
becomes 0/1)