I don't know if it's true or not, but my cousin told me there's a FOURTH regi called RegiGIGAS who is normal type and is stronger than all the other three combined. You need to put all thre regis in ur team then go to the cave where regice was during the day and give it an icy item like a casteliacon, nevermeltice, etc and nickname it ICEE (all caps). Once you enter a message will ask you if you're prepared to fight the king of the regis, choose YES and Regigias will show up at level 100 and it knows Hyper Beam, Giga Impact, Judgment and Ancient Power. BTW not even the masterball will work on it you need to use premier balls to catch it.