* FandomLifeCycle: Along with its related series 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.
** Dr. Arewo Stein from the [[NoExportForYou Japan-exclusive]] GameBoy game ''VideoGame/ForTheFrogTheBellTolls'' makes several appearances in ''Wario Land 4''.
** In a more literal sense, the music for the first level of "Shake It!" makes a couple of appearances in ''VideoGame/SuperSmashBros Brawl'': as Wario's victory fanfare, and as part of the [[MarioKart Waluigi Pinball]] track
* NamesTheSame: ''Wario Land: Shake It!'' has a level called [[VideoGame/PaperMario Mt. Lava Lava]].
* WordOfDante: While it's never been mentioned in the games, ''Famitsu'' magazine has claimed Syrup's first name is [[PunnyName Maple]].