Grate Guy's Casino
From the Super Mario Wiki
Grate Guy's Casino is a secret area in Super Mario RPG: Legend of the Seven Stars. The casino is run by the jester Grate Guy, and can only be accessed with a Bright Card acquired from his partner Knife Guy.
The casino can be entered through a secret passage in Bean Valley. In one of the pipes in the center of the valley, Mario has to defeat a Chomp Chomp and jump three times to make an invisible platform appear, which opens the way to the casino. Mario can get hints on how to find the casino from a sleeping Toad in Nimbus Land's inn.
One game available is the slot machine. Mario has to set a number of coins, then hit a Treasure Box three times, stopping it at the same symbol each time. If he manages to, he is awarded a Frog Coin. Another game is Blackjack, played with the normal rules; the player plays against the dealer, and the one who comes closest to 21 without going over wins. The third game is Look the Other Way. This is a simple game where the player picks a direction to face, and if they look in the opposite direction as Grate Guy's finger, they win. The Star Egg can be won by beating this game 100 times.
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