My friends and i are making a halo short film for our cinamatography class and for the brutes right now all we really can do is convert my friend's gorilla costume into a brute costume, it turned out pretty good, but i still need some other ideas.
Its going to be hot. Very hot. Make absolutely sure that you hide a large camel pack, or even two underneath the costume. Provides water and makes you look buffer which would help in this case since brutes are behemoths.