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• A second player can join in at any time, and will get 5000 free crystals if he does.
• In a 2-player game, the projectile-firing enemies will fire twice as many projectiles, and the bosses will take twice as many hits.
• If you win a weapon from Dream Co., Ltd. and turn it down, you will get it the next time you are killed.
• If you have the stock bomber shot, don't let Pac-Man suck in too many of the enemies' shots - he will return to his normal size if he does.