After completingthe game on X-Treme difficulty while the credits are rolling, you'll be in an arena type setting with an unlimited amount of enemies spawning. If you defeat 200 enemies before the credits stop rolling, you will unlock the Vintage Suit.
ACHIEVEMENT - HOW TO UNLOCK Think About It... (20 points) - Make first power destiny choice. Destiny Begins (15 points) - Select a Power. Choose Wisely (20 points) - Make second power destiny choice. The Choice Is Made (20 points) - Make third power destiny choice. Got My Eye on You (30 points) - Join Cyclops and the X-Men. Magneto Is Right (30 points) - Join Magneto and the Brotherhood. Splicer (10 points) - Equip your first X-Gene. At Least It's Aerodynamic... (10 points) - Equip your first suit. I've Got the Power (20 points) - Fully level up a power. Fully Evolved (30 points) - Fully level up all powers. Four of a Kind (20 points) - Equip a complete X-Gene set and suit. Beginner's Luck (10 points) - Complete your first Great combo. This can't be happening! (20 points) - Complete your first Insane combo. How Strong Could It Be? (20 points) - Trigger X-Mode. Broken Glass, Everywhere... (20 points) - Break 30 Combat Text Pop Ups. Fight Terror with Terror (20 points) - Defeat 10 enemies with one Ultra power. Side-tracked (10 points) - Complete your first challenge mission. Taking Every Opportunity (25 points) - Complete 10 unique challenge missions. Completionist (50 points) - Complete all 15 unique challenge missions. Garbage Collection (10 points) - Destroy your first piece of propaganda. Cleaned up the City (30 points) - Destroy 25 pieces of propaganda. Profiler (10 points) - Collect your first dossier. Archivist (30 points) - Collect 15 dossiers. Purify the Purifiers (20 points) - Defeat 2000 Purifiers. Mechageddon (20 points) - Defeat 20 Purifier Stalker Mechs. Reinforced (20 points) - Defeat 20 Prime Enforcers. U Mad, Bro? (20 points) - Defeat 30 U-Men in the Secret Lab. The Goon Squad (20 points) - Defeat 500 MRD Troops. Alpha Level Mutant (50 points) - Finish the game on X-Man difficulty. Omega Level Mutant (50 points) - Finish the game on X-treme difficulty. Can I Get A Valkyrie? (0 points) - You were defeated 100 times. Beta Level Mutant (50 points) - Finish the game on New Mutant difficulty.