* FandomLifeCycle: Along with its related series ''VideoGame/WarioWare'' and the other ''Wario'' games, probably one of the only series that both sells more than a million copies and yet is still somehow in phase 1 of the list, with it somehow having nothing of an organised fandom. [[http://nintendo3dsdaily.com/nintendoarticles/why-doesnt-the-wario-series-have-a-dedicated-fanbase/ Various people]] have questioned exactly why this is.
* MarthDebutedInSmashBros: Dr. Arewo Stein from the [[NoExportForYou Japan-exclusive]] UsefulNotes/GameBoy game ''VideoGame/ForTheFrogTheBellTolls'' makes several appearances in ''Wario Land 4''.
* NamesTheSame: ''Shake'' has a level called [[VideoGame/PaperMario64 Mt. Lava Lava]].
* WordOfDante: While it's never been mentioned in the games, ''Famitsu'' magazine referred to Captain Syrup as "Maple" in a ''Shake'' preview, implying that her full name is [[PunnyName Maple Syrup]].