Dirty Rat will be the Boss in this level. Continue through the maze and find the checkpoints. the last will have power-ups next to it. When continuing through the maze you will find mirrors. If you find them you will be on the right path. When you get up the levers, you will find the checkpoint. Get the power-ups and get ready to fight Dirty Rat. As usual, use any attacks against him. After you kill him Ace will say "Hope you loved that as much as I did, Rat!" After that collect your points and save the game.