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Games that intend to be practicing tools for improvisation may interestingly serve different purposes depending on a genre context.
Classical approach
Jeffrey Agrell wrote books about music games for classical musicians (for example Music Games for Classical Musicians) with simple open-ended activities, often consisting of a single rule to follow. One of the proposals is Dueling Bumblebees.
There is one rule: Improvise using only semitones.
This simple activity provides a challenge for improvisers, and also let's inexperienced players make safe first steps into improvisation. The horizon of intent is not overwhelming and the musical result is coherent and somewhat familiar to classically inclined users.
The set of games from Agrell's book makes the whole learning program, and during the course of it, rules slowly introduce players to openness of improvisation and let them gain confidence within the more interactive, bottom-up oriented environment. Games on one hand provide the lighter mood and they also structure the experience and act as a safety net. In the practice of classical musicians, improvisation is rarely a directly useful skill, but it may be considered a worthy didactic tool to deepen the understanding of music.
In jazz
In jazz, similar general didactics have in a way an opposite aim. Here the abundance of personal expressiveness is assumed, but intellectual control is what is being practiced. In the video below, there are example of constraint that need to be followed while improvising a saxophone solo to strengthen this ability.
Comping Game
In a similar fashion Peter Erskine's Comping Game is another example from jazz although related directly to drumming.
The game is played with a drum set. Keep the consistent swing pattern with your ride cymbal and hi-hat foot (pictured) and occupy your other two limbs with as diverse playing as you manage while following additional rules.
In the first round you may only interchange one note on a kick drum with one note on a snare drum. If you play any of your limbs two times consecutively, you loose the round. You also loose round anytime you mess up the swing pattern while trying to add notes.
In further rounds the amounts of repetitions for an instrument change to different combinations. Second round is one kick, two snares (hitting one snares between to kicks causes loss etc.), after that prescribed pattern is 2 kicks one snare, then 2 for 2…
If you want to play many rounds go (from the start) for nine rounds of: 1-1, 1-2, 2-1, 2-2, 1-3, 3-1, 2-3, 3-2, 3-3.
Best to play with a timer for every of the rounds.
It's quite a traditional take on jazz drumming intended to give solid basics to a historically the most important style.
Among many genres
Many improvisational genre types (like raga, flamenco, gnawa etc.) follow the analogous procedure and may have a few interesting common features:
- learning to improvise within these genres, means to improvise while adhering to the genre constraints ("genre as a game" situation, see genre),
- didactics may consist of keeping the genre constraints while practicing patterns, defined in detail or more loosely, of gradually increasing, but theoretically uncapped difficulty (it may be shaped into the perfect learning curve),
- rules of interaction between players may belong also to genre constraints,
- the most appreciated artistic qualities are not taught directly with a didactic process, but are possible to realize in the advanced stages of it.