You advance on the board by holding A. Once his hollow triangle starts moving you need to keep your black triangle within it by going left/right on the D-Pad. If you're not you will stop moving. There are two types of games: Rock-Paper-Scissors and a Red Light/Green Light timing game. The following strategies below are fast strats for Rock-Paper-Scissor, the timing game is RNG.
[For Rock/Paper/Scissors] The patterns assume you complete them the fastest without error. Keeping within their triangles while moving shouldn't be too difficult. I am not sure if the patterns recycle.
[For timing games] Hold A while the boss speaks, when he says "darumasan ga koronda" [だ-る-ま-さ-ん-が-こ-ろ-ん-だ] you can move on the board the most. Just remember all the other speeches the bosses do are short, and quick. Memorize them, expect them. Timing is key. Remember to keep your triangle within his as well. If you screw up it costs you 3 eggs, lose them all you restart. So if you have many for the final boss just tank it lol.
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Scissors only
Timing game.
Timing game.
Paper - Rock - Scissor - Rock - Scissor
Scissor - Scissor - Paper
Scissor - Scissor - Scissor - Paper
Rock - Rock - Rock - Scissor - Paper
Timing game.
Timing game.[/center]