Bertwalker

{b}: Muppets gain +1/+0 until end of turn.
{b}{b}: Target creature becomes Muppet
while Bertwalker is in play.
{b}{b}{b}: All creatures become Muppets
while Bertwalker is in play.
{b}{b}{b}{b}: Destroy all Muppets.
"Are you awake, Bert?" " I am now"