Deadpool keeps piling on the Marvel characters. Today High Moon announced that the merc with the mouth will be joined by two more notable names from canon: the X-Men villain Mr. Sinister, and the telekinetic ninja Psylocke.
The announcement doesn't mention their roles in the game, but we can glean a little from Marvel history. Sinister is a telepath and scientific genius who has weaved in and out of the lives of various X-Men, including Cyclops. His interactions with Deadpool have been limited, but Deadpool began in New Mutants, which was itself a spin-off from the X-Men books, so the worlds aren't entirely disconnected. Psylocke, a member of the X-Men, is yet another telepath and a master martial artist. Like Sinister, her interactions with Deadpool have been brief.
Deadpool is due on June 25, for PC, PlayStation 3, and Xbox 360.