As of today, playing your Steam copy of BIT.TRIP BEAT results in something kind of strange and awesome happening: it’s been infected by Portal‘s GLaDOS, who has added an entire new level to the game. Worse still, it appears that BEAT is not the only victim of GLaDOS’ bizarre machinations.

But first, here’s some footage of what she’s done to the Gaijin guys’ game. Peep the trailer embedded below for some idea of what to expect:

BEAT wasn’t the only Steam game to receive a weird update today, though. A ton of titles from the 13-game indie bundle The Potato Sack have received strange, largely unexplained patches. Among the changes included in these patches are a “new expansion” for Amnesia featuring ”20% more horror and 10% less cake,” seven new stages for The Ball, Companion Cube blocks in Rush, and a Chell-themed ship for Audiosurf. Huh.

If you want up-to-the-minute updates on what exactly is going on here, launched a Twitter account an hour ago called @PotatoFoolsDay for keeping up with these Potato Sack shenanigans. According to Gaijin’s blog post, the endgame in all of this is potentially getting Portal 2 released early, which is an exciting prospect for everyone! Well, everyone who plans on getting the game via Steam, at least.

Since most of this has gone down in the past couple hours, there is still plenty of stuff to be uncovered. Me, I’m gonna go dip into my Potato Sack games and see what’s been changed. Exciting!