Ecco the Dolphin: Defender of the Future Cheats (Dreamcast)

Encounter the Boss in the "Blades..." level. It is a large room with a Boss that resembles
a large dragonfly larvae. Go to the bottom of the room where you can refill your air
supply with the bubbles coming out of the ground. Next to the bubbles on the floor near
the wall is a small hole. Go through it and get outside the game world.

Press Start to pause gameplay, then press X + Y.

Hold X (sonar) during gameplay for a long time. Press X again to return to normal.