Earlier this year, Will Ferrell [1] challenged Red Hot Chili Peppers drummer Chad Smith to a charity drum-off after Will pretended that he was Chad [2] during a Reddit AMA. (You have to admit, the two have a very strong resemblance to one another.) Chad agreed, and, after months of hilarious smack-talking, the two finally did their drum-off on The Tonight Show. Watch their drum-off — along with an appearance by some very special guests — above, and watch the two look-alikes talk about their intense rivalry in a hilarious interview with host Jimmy Fallon [3] below.