Nick Collison's birthday is on Monday. In celebration, he held a Halloween party that's become a tradition the past couple of years.

Most of the costumes were pretty creative, with Nick Collison as Forrest Gump, Mitch McGary as a member of Average Joe's from the movie Dodgeball and Steve Novak in an ape costume.

But the winner of best costume, clearly, goes to Russell Westbrook, who went as Thunder center Steven Adams, tattoos, long hair and all.

Here he is standing next to Adams, who was dressed as the Joker from Batman: