Snakegirl Doppelganger

You may have Snakegirl Doppelganger enter the battlefield as a copy of any creature on the battlefield, except it doesn't copy that creature's color and it has "At the beginning of your upkeep, you may have this creature become a copy of target creature, except it doesn't copy that creature's color and it has this ability."
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)