Some of the best gamers in the world have gathered near Washington, D.C. this week, and some have fingers so fast, your mind probably won’t have the capacity to handle it.

StepMania is a rhythm-game engine for the PC capable of handling arcade hits like Dance Dance Revolution and more. But, unlike with DDR, you don’t have to play with your feet, and that means fast-fingered players can attempt (or even perfect) songs that are typically impossible. And we got an example of that during Awesome Games Done Quick, a speedrunning marathon that’s happening right now on Twitch, when Stepmania master Staiain took the stage.

Staiain booted up the game on his laptop and proceeded to demonstrate a level of skill and accuracy most players will never even come close to. You’re just going to have to check it out for yourself to see what I mean:

To give you an idea of the speed involved, Staiain is hitting around 25 notes or keys every second. That even puts the fastest StarCraft II players to shame.

The rhythm-game section of AGDQ is over now, but you can catch some awesome runs for the rest of the week, including a huge Mega Man block happening all through tonight. And you should tune in, since this marathon is all about raising money for the Prevent Cancer Foundation. So far, since Sunday, these skilled gamers have raised nearly $500,000 for the charity.

Check out the livestream below: