Mario is on an Italian tour bus when they see Homer. Mario wants his picture taken with Homer who then proceeds to throw bins at him (in a reference to the original dkwiki:Donkey Kong game). Mario then climbs up the treehouse, gets a hammer and begins to destroy the bins before he is finally hit and falls down.
When Luigi wins an auction for old video games, he exclaims "It's-a me!". His brother, Mario Risotto, then asked him to help fix a leak. Luigi told him to "hold your mushrooms".
The quest name "It's A-Me, Luigi!" is a reference to Mario's catchphrase "It's A-Me, Mario!"
In the Tap Ball and Soccer Cup 2015 update if two Tap Ball teams of identical players face off, there will be a joke about alternate versions of themselves. An alternate version of Luigi appears, called Waluigi, referencing the Mario character.