While this is mainstream music, this isn't the sort of thing you will get in trouble for in particular because this game as been out for a while. What most don't know is that the two mixes of Imma Be used here are either really rare or unique to this game. Imma Be (Fast Version) is definitely unique because I don't recall the super fast arrangement of the first of Imma Be in the second half.

So basically someone took the one part everyone likes in Imma Be, turned it into a song as long as Imma Be, and never released it to the public.

Dang it, Ubisoft. -.-