As if Boston Dynamics's robotic pack mule wasn't terrifying enough, its designers have, in their infinite wisdom, equipped it with a throwing arm. But not just any kind of throwing arm. This thing's a total cannon — one that would make Peyton Manning jealous. Check out the video and watch BigDog toss a cinder block across the room like it was a Nerf football.

We're not entirely sure why a mechanical pack mule needs to be able to throw stuff. But hey, Boston Dynamics is doing its damnest to ensure the most nightmarish robopocalypse possible.

Update: An earlier version of this article noted that DARPA was involved with this add-on, which isn't the case. Rather, it's U.S. Army Research Laboratory.

H/t Engadget.