Puyo Puyo Tetris and How it Pays Tribute to the History of Both Games

As a crossover between two great puzzle game franchises, naturally Puyo Puyo Tetris makes references to the history of both series.

Characters

• The Tetris characters are astronauts. This is in all likelihood a reference to the ending of the Game Boy Tetris game, which depicts a rocket launch.
• There are 24 playable characters, as is the norm for the Puyo Puyo series.

Modes

• Big Bang is like Non-Stop Fever from the Puyo Puyo Anniversary titles, except with, among other things, health bars instead of a set amount of Garbage Puyo each player needs to neutralize (that's the term Sega seems to be going with in the West instead of offset).
• Apparently Big Bang returns in Puyo Puyo Chronicle (The following game in the Puyo Puyo series, released for the 25th anniversary) despite Non-Stop Fever also returning, except with the Tetris elements removed for obvious reasons.
• This one is a stretch, but Party Mode is a bit like Slot Mode from Puyo Puyo 20th Anniversary. It uses Fever dropsets (with the Tetris characters notably using the dropsets of characters who only make cameos) and heavily involves item RNG. Also just like Slot Mode, it is terrible. Why would you pay tribute to Slot Mode of all things?
• Far less of a stretch is that two of the items in Party Mode, Frozen Puyos and Searchlight, are references to the Ice Blocks and Searchlight game modes from the Puyo Puyo Anniversary games.
• There is also an item which turns Tetris opponents' pieces into pentominoes. Tetris was inspired by pentomino puzzles, so if this was an intentional reference, then it is a pretty well-thought out one. Then again, I am calling something in Party Mode "well-thought out".
• Among the Challenge modes is Endless Tiny Puyo. Outside of certain stages in Adventure Mode, this is the only time Tiny Puyo is used.
• The Tetris Challenge modes are Marathon, Sprint, and Ultra, possibly the three most recognizable ways of playing Tetris, and definitely among the oldest.

Music

• There is a mix of music from both Puyo Puyo and Tetris, and the Tetris music does not just consist of variations of Korobeiniki (I had to look that up) as you might expect. The default BGM for the Tetris Challenge modes is actually from Sega's own Tetris game!

Skins

• The vast majority of the Puyo skins are from previous games in the Puyo series, though that admittedly may just be laziness. In fact, there is only one that is new.
• You can also unlock various backgrounds from certain games in the Puyo Puyo series. 
• And also one that is from Sega's arcade version of Tetris. It is very different from every other background in the game. You will know it when you see it, hopefully.
• You can unlock a Game Boy Tetris skin, and some other well-known tetromino designs are available from the start.

Puyo Puyo Tetris, as a crossover, references the history of both series in many ways, as seen in the examples above.