Last year, DARPA unveiled Cheetah: a robot that could run faster than Usain Bolt. Now, the same team has managed to create a version that doesn't need a power cord, making the electronic beast free to roam wherever it chooses. Be afraid. Be very afraid.

A relative of Cheetah, say hello to WildCat. This robot is based on the same design as Cheetah, but doesn't have the tethered power cable of its predecessor; instead, it has a large—and quite loud!—motor attached to it.

That extra weight does means it can't quite match the pace—Cheetah can reach 28mph, while WildCat can only manage 16mph. But, hey, given that's faster than most of us can run, it's not too bad. And remember, WildCat can keep up that speed for as long as it motor runs, which humans definitely can't.

The Pentagon's Super-Fast Robot Now Runs on Its OwnS

Certainly, it's fast enough to chase you, and perhaps catch you, and maybe even kill you. All without a wire in sight. We're all going to die, guys. [Boston Dynamics via Engadget]