Having learned the whereabouts of the next member of the Fiendish Five, Sly and the gang head out to Mesa City, home of the notorious Muggshot.
Head through the pipe and hang a right down the path to the bridge. When you get there, you'll see Muggshot's casino and realize he's probably in the fire hydrant at the top. The flashlight enemies here are pretty tough, so be careful to stay outside the range of their light. If you have the mine hat, you can use it to kill them by placing it down when their backs are turned, then detonating it as they walk over it. There are three levels accessible from this area, and when you have four keys you can move on.
- At the Dog Track: By the Boneyard Casino entrance, take the ramp up to the right and then Ninja Spire Jump across to the other side of the area.
- Murray's Big Gamble: As soon as you cross the bridge in the beginning of the area, head right through the subway car.
- Boneyard Casino: In the far right corner of the area there's a big neon sign with arrows where it says "BONEYARD".
With four keys, head to the platform next to the red car with the spinning wheels in the center of the area. This will unlock the jack the car is on so you can hit it and the car will crash into the casino, opening up an entrance for you. From inside you can access three more levels, which will give you the keys you need to unlock the passage at the front desk.
- Back Alley Heist: Go up the stairs and head right. Instead of going to the top, climb the cord on the side and take the spires and lights across to the other side.
- Straight to the Top: Go up the stairs and take a left to the higher landing. Use the mattress to get up on the spires above and use them to jump over to the entrance.
- Two to Tango: Head up the stairs and take a right up to a roving flashlight guard. When he's facing away from you, run up and take cover behind the trashcan, then run over and take him out.
With all the keys in your possession, head down to the front desk and open up the secret compartment, then hit the switch to reveal the secret elevator up to the boss' lair.