Here's my idea for the jam:
"GUNSEED!" an explosive fps where you shoot SEEDS into the mud,
blast WATER onto plants, MACHINEGUN pollen everywhere,
toss plantfood GRENADES, and reap the souls of wheat with your razor sharp SCYTHE
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Another fun idea would be "INSULT FIGHTING"inspired by Monkey Island Sword Fights
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Or how about cake or ice cream decorating with icing blasters and sprinkle cannons!
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Or how about an ARCHERY GAME starring cupid?
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Or a NATURE PHOTOGRAPHY game with a telephoto zoom sniper mechanic!
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Good luck!