He can currently Ult even while CC'd by 
ult. But I'm not quite sure if it translates to roots as well since his basically is a root that removes AAs. But him being able to ult out of is definitely not intended.
Interesting.
So you are saying that Graves is in fact able to cast ult (which he should be able to), but his ult also moves him even when he is affected by amumu's ult (which should not happen, similar with caitlyn net)?
This deserve some attention indeed.
Bump for Riot.
Bumperino #2
It comes from Grave's Ult not originally marked as a dash to be stopped by Roots/snares/immobilizes. I don't know if riot wants to keep it, since it may be coded as self inflicted knockback instead of a dash.
