However, you'll soon learn that Grate Guy's Casino is for members only! How to get the Bright Card & enter Grate Guy's Casino
A previously invisible platform will appear, which you can use to leap atop the green-bricked wall and enter a secret passageway that leads directly to Grate Guy's Casino. Best the Gold Chomp, then move into the upper-left corner where the Chomp Chomp was chained up and jump three times.
Inside the Warp Pipe, you will notice a Gold Chomp. Once the Fly Guy waters the Piranha Plant in the top-centre Warp Pipe, approach it and do battle, then enter the Warp Pipe after you defeat it. As you trek through Bean Valley, you will eventually come across a circle of Warp Pipes occupied by wilted Piranha Plants. The journey to Grate Guy's Casino begins in Bean Valley in the Land's End Region. Grate Guy, an associate of Booster, owns and operates a casino, but it's nearly impossible to find if you don't know what you're looking for.
Believe it or not, the tales of a hidden casino that the Toad in the Nimbus Land Inn tells in his slumber aren't a bunch of baloney.