Note: This game includes English and Japanese. For a preview, English rule can be found here.
Take The "A" Chord, a.k.a. Aコードで行こう, is a trick-taking card game in which players become jazz musicians and compete in the strength of the chord.
Cards come in five suits (colors) labeled A-G, and in a trick, you must play a card of the same suit led — unless you have a card in the same letter as a card previously played, in which case you can play that. Why would you do that? Because initially the highest-valued letter in the game, e.g. C, is determined randomly, with the other cards being ranked lower in C in order: C is higher than D, which is higher than E, etc. with G higher than A. When you play the same chord — that is, letter — as another player, you make that chord the new highest-valued letter for subsequent tricks.
What's more, if you play the same chord as the player who started the trick — that is, if you improvise — not only do you change the highest-ranking chord, that trick goes unresolved and you start a new trick with the winner of that trick taking all tricks played since multiple instances of improvisation can take place.
You score a bonus for improvisation, but you don't want to take too many tricks in a round as that will cost you points in the long run. Score well, lead the band, then step aside for others to (possibly) take things too far. After multiple rounds, the player with the most points wins.
The 2015 edition of Take The "A" Chord included rules only for three and four players, while the 2021 edition contains larger components and rules for 2-4 players.