Fluttershy, Friend to Animals

Whenever you cast a creature spell, create X 1/1 rabbit creature tokens, where X is that creature's converted mana cost. At the beginning of your end step, create your choice of a 1/1 rabbit creature token, a 2/2 bird creature token with Flying, a 3/3 serpent creature token with reach, or a 4/4 bear creature token with Trample.