To get the Boss Car, press L + R + Up at the title screen. If you did the trick correctly, you'll hear a
rumbling sound. Begin a normal game. When you reach the boss, you'll be driving his car.
At the title screen, press Up, Down, L, R, Select. If you've done the trick correctly, you'll hear an
explosion in the background. Now go to the Options menu and choose Mystery Mode. You'll be able to play the whole game from an overhead view.