This page explains in detail the interactions between the Tetris series and the Wario series.
WarioWare: Smooth Moves[]
December 2, 2006
Tetris
Wario
9-Volt and 18-Volt's microgame "Opening Night" features some Nintendo characters playing musical instruments. Many feel this to be a reference to the ending of Tetris on the NES, most notably for Samus playing the Cello. Anyway Link and Pit's instruments are different, so it might be a coincidence.
Tetris 99 - 24th Maximus Cup[]
September 17, 2021
Tetris
Wario
A theme based on WarioWare: Get It Together! was added to Tetris 99 as a reward in the 24th Maximus Cup from September 17 to September 20, 2021.
License[]
Nintendo only included a minor reference to Tetris in their game, so they didn't need any license.
