Team Fortress 2 is getting playable robots. That, at least, if a series of teases and fan sleuthing operations are to be believed. The first clue came directly from the Team Fortress 2 official website itself. Click on the bloodstains on the site, and you will be delivered to this mysteriously URL, which hosts a cryptic note. And then there's this strange comic, currently sitting at the top of Valve's Team Fortress 2 page.

Shortly following this discovery, a group of NeoGaffers took the plunge on trying to decipher the note and reveal its implications for the game. Through a series of logic jumps that, to an outsider looking in, probably sound completely mental (but to a Valve fan are in fact relatively normal,) they came to the conclusion that this was all related to the Man vs Machine update which has been rumored to be coming to Team Fortress 2 for, oh, around two years now. This update would include playable robots.

The investigation is actually rather in-depth and relies heavily on in-game evidence going back upwards of two years. Due to the complexity of it all, we refer you to this fan-made video compiling all of the evidence. While Valve hasn't confirmed or denied anything about the note yet, it seems pretty likely that this is what it'll all be about in the end.