What's the worst video game you've ever played?

Probably Call of Juarez: The Cartel. I wanted to play the entire franchise back to back, but it wasn't being sold on Steam, so I had to hunt down a copy on some key reseller. Boy, do I see why it's not on sale anymore. runs like absolute shit, incredibly buggy, cheesy as hell and with some pretty questionable game design choices. Still, it was somewhat entertaining in a "so bad it's good" sense, and it ties into the previous games in a fairly interesting way, so I don't regret playing it. It was certainly an experience, but it's a very bad game by pretty much all metrics.