True unblockable discovered in Super Street Fighter 4 Arcade Edition v2012 - the inescapable Ultra
@ 44 Edit, it was a reply to 20 and 39

True unblockable discovered in Super Street Fighter 4 Arcade Edition v2012 - the inescapable Ultra
@ 26 & @39 Rufus' target combo, Gen's super, Gouken's back throw and Cammy's Quick Spin Knuckle all put the opponent into a juggle state where Ultras can, and are supposed to, juggle them. This new Claw setup is an exploit of the game's blocking mechanics.

Street Fighter 4 update balance change requests from Japan, part 8 - Rufus, C. Viper, Abel and Dan
All Dan needs is for his Koryuken to launch the opponent further forward, he's really solid otherwise.