Forward-looking: Do you have ambitions to become a Doc Ock-style supervillain sporting robotic limbs? We might have taken the first tiny steps toward that worrying fantasy with a robot third arm that’s strong enough to punch through walls.

As reported by IEEE Spectrum, the arm is the work of researchers from the Université de Sherbrooke in Canada (in partnership with Exonetik) and was shown off at the recent International Conference on Robotics and Automation.

The hydraulic device has three degrees of freedom, can move at up to 3.4 meters per second, and is able to lift five kilograms. It’s also light, weighing just four kilograms, and, as the video shows, can punch through a wall—though the wearer gets shaken around quite a lot.

There are a few caveats for wannabe bad guys to consider. The wearer is tethered to a large and clunky power system, which is definitely going to limit mobility, and the arm is controlled by a second person using a miniature version of the robotic appendage. Eventually, however, the power pack could be converted to a backpack, and sensors could allow it to perform simple tasks autonomously, such as providing tool assistance.

The project has the goal of “mimicking the performance of a human arm in a multitude of industrial and domestic applications.” While it’s far from perfect right now, the arm can show the sort of issues these devices face. Being able to attach four ultra-powerful robot arms onto your back is a long way off, but we all must start somewhere.