Like in Tetris players must carefully fit sound between other sounds that drop into a pre-planned number of measures. No overlapping! Quick game that requires focus, tight rhythm and a bit of musicianship.
Setup
Decide on how many measures to loop. From 2 - 4. Choose an order for each player to play. Stay with that order for the remainder of the game. (It's best to sit or stand next to each other in that very order).
Gameplay instructions
Everything must be played between sixteenth and quarter notes. No less - no more.
Everything a player plays must be repeated exactly the same way at the same spot in the loop for the remainder of the game.
Players are not to play over anything else. No overlapping of any kind.
Everything played will continue in a manual loop played by the players (no loop pedals) until the end.
See the example below to help further explain the approach.
Game end
If a player makes a mistake then everyone stops and tries again from scratch.
Once all the empty spaces are filled the game is over.
It’s fun to play the final form a few times before ending as a celebrated theme of glory!
Gamemaster's notes
I’ve found that a medium tempo is easier than a slow tempo.
Personal note: I really like when this game uses all synths!
Example
In this example let’s say we have four players. They decided on a two bar loop.A player can play any kind of sound - a musical note, untuned percussion, noise, ect. For his example everyone will play notes.
Player #1 starts by playing something anywhere within the chosen number of measures.
The loop begins:

Player #2 follows:

Player #3:

Finally player #4:

Now we come back to player #1. This player now plays his second note:

And this continues until there are no more spaces left and the loop is filled with no overlaps. The final product:

As stated in the rules, it's fun to repeat this a few times to celebrate the glory of completing this round of the game with no mistakes:

Variant
Musical Tetris lvl 1 is a much easier version suitable to play also with non-musicians.
Comparing to the main variant, the simplification is played only with quarter-notes, or even with the agreement that every player entry takes a length of a quarter-note in the bar, even if played longer (or shorter).
Editor's notes
Photo used for decoration is "Tetris" by Cotopaxi, CC BY-NC 2.0.
The game in this form gives you uFor a simplified version, see: Musical Tetris, lvl 1
Designer-composer
Marcus Staniec (notrightmusic)
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