Worlds United: The Ultimate Crossover

Super Smash Brothers X Kingdom Hearts: The Next Chapter is a huge collaboration between Nintendo, Sega, Capcom, Bandai Namco, Konami, Ubisoft, Activision, The Walt Disney Company, Final Fantasy, and The World Ends With You in the crossover.

gameplay
you can play as the fighters of the Super Smash Brothers video games, and you can also play as the key blade wielders as well.