Strikeforce: Heavy Artillery: World Heavyweight Champion Alistair "The Demolition Man" Overeem (32-11) will make his highly anticipated return to action against heavy-handed knockout artist Brett "The Grim" Rogers (10-1) in the main event of a STRIKEFORCE mixed martial arts (MMA) extravaganza at Scottrade Center in St. Louis, Mo., on Saturday, May 15. In another heavyweight confrontation, Andrei "The Pitbull" Arlovski (15-7) will clash with Antonio "Big Foot" Silva (13-2).