Wraith of EU-Ysondre has been hard at work toppling the hard modes required to access Algalon the Observer, the true final boss of Ulduar. They've yet to defeat Agalon, but they're one of the first guilds in the world to even see this boss in person.
MMO-Champion has a whole load of pictures from their raid, and I have to say... they're pretty trippy. It makes the psychedelic blues of the Malygos encounter look tame in comparison. The encounter also has an added hook to it: Upon reaching his chamber, you're given 60 minutes to fight him. After those 60 minutes, he despawns for the