On the left is Red Hot Chili Peppers drummer Chad Smith. On the right is actor Will Ferrell. The lookalikes have a bit of a "feud" (chronicled here: http://www.funnyordie.com/lists/ce4df3b78d/will-ferrell-is-chad-smith-from-the-red-hot-chili-peppers?ts=1391722206) and they're ready to duel.
Here's what Ferrell posted on Reddit:
Hi, Chad. Will Ferrell here. I saw your video and I graciously accept your invitation to a drum battle. If we can raise $300,000 for Cancer for College I will face off with you in the greatest drum vs. cowbell showdown the world has ever seen. We can do it on stage at a Red Hot Chili Peppers concert or in front of a mutually convenient public library. Your call.
I'd watch that.