Six Flags Universe, located in the park's USA section across from Bugs Bunny Boomtown, is the largest indoor shop. The location also home to Roller Coaster Coffee. Shop items include Six Flags, Looney Tunes and DC Comics-related merchandise.

This structure has existed since the park opened in 1961. Prior to being home to various shopping locations and other experiences, the building featured several corporate-sponsored exhibit halls. Before its transformation in 2022, the location was known as Looney Tunes Mall. It featured a large, cartoon-like facade with both Looney Tunes and Justice League characters.