Murderworld appears in Marvel: Ultimate Alliance.
Rather than being a single location, Murderworld is the name given to the fairground/amusement park-style deathtrap used by the assassin-for-hire Arcade. Utilizing sophisticated robotic and holographic systems, Arcade has frequently pitted various superheroes against Murderworld, sometimes for money and sometimes merely for the challenge. Arcade has built Murderworlds under Manhattan, on a Caribbean island, in Antarctica, in England, and numerous other locations around the world.
Marvel: Ultimate Alliance: Story
When the heroes used Doctor Strange's Orb of Teleportation to travel to Castle Doom, they were diverted by Baron Mordo to Murderworld where they arrived in a fake Castle Doom. It was also revealed that Arcade has Senator Robert Kelly in Murderworld and Jean Grey was shown to be under Arcade's mind-control when found in a tent. The heroes fought their way through Rhino and Shocker where they end up fighting Arcade in his Arcade-Bot. Some of the Simulation Disks take place in Murderworld. In Deadpool's disk, he is irritated greatly by Deadpool's refusal to accept that Murderworld isn't a normal theme park (although this probably is Deadpool's taunting rather than an actual lack of understanding, Deadpool's borderline insanity makes this uncertain), and forcing the mercenary to fight Dark Spider-Man (who Arcade referred to as his creation). In Black Panther's disk, Arcade was threatening Black Panther to give the secret codes to Wakanda's vibranium facility (which of course he doesn't tell) and forcing Black Panther to fight Dark Captain America. Storm's disk has her fight against Hussar in Murderworld. The versus Mysterio simulator takes place in Murderworld. Mister Fantastic's disk has his fight against Bulldozer in Murderworld.