Various characters from the WarioWare series make cameos throughout Rhythm Heaven Groove:

• At the start of Sneezy Moon, Ashley has a chance of appearing amongst the swarm of bats, using her design from Game & Wario. This is hinted at by the "Magician in the Night" Info Tidbit.
• During Soccer Dreams 2, Mona has a chance of appearing on the bench behind Sora, wearing her cheerleader outfit from WarioWare: Smooth Moves. Similar to Ashley's cameo, this is hinted at by the "Benchwarmers" Info Tidbit.
• In the Try Again epilogue of Synchro Wings 2, the Alien Bunnies appear piloting the UFO that the Migrating Birds are resting on.
• In the Good epilogue of Pet N Parcel 2, one of the Sasquatch Family members from WarioWare Gold is shown accepting the package from the rabbit.