Beast Boy still has a lot more... He can even turn into fictional creatures. As long as he knows the creature he can turn into it. 

I'm Sorry Mike, but I just can''t accept you... I haven't really seen you in a good light and cannot take the chance right now. And it hasn't even been THAT long for you to change... I have a list of problems with some of the RPing I've seen you do and I just can't bring my self to allow it... I'm sorry if I sound like a jackass, but it is how I feel.