The World’s Deadliest Game

Brainiac plans to use an invisibility device to trick Black Vulcan, Wonder Woman and Hawkman onto an artifical planet ruled by The Toyman and inhabitated by deadly toys in a black hole while the Riddler lures the other Superfriends into different traps so the Legion of Doom can take hold of the World's national treasuries. The Superfriends solve the Riddler's riddles and Green Lantern rescues the members just before the black hole closes. However the Legion turns invisible to escape.