"Yasai Game" is a falling object puzzle game that incorporates physics calculations. Players can evolve yasais by dropping different types of yasais into boxes and making them come into contact with each other. A total of 24 types of yasais appear, and the game can be cleared by making the cabbages and pumpkins touch each other.
A characteristic mechanic of the game is that combos occur when yasais evolve in a short period of time, and by making combos happen continuously, "helper" appear that are advantageous for gameplay. This helper character will stir up the Yasais in the box, giving you a chance to turn the game around once and for all.
"Yasai Game" has a time attack element where you aim to clear the game in a short time, a high score element where you aim to get the highest score, and a challenge element where you compete to see how far you can evolve your yasais. These can be competed on online leaderboards.