Your little yellow research sub is moored over the reef. Giant clams hide ten pearls across the coral gardens, the kelp forest, and the bottom of the Blue Hole. A captain's chest lies in the wreck to the east. Bring it all back to the sub — swim it, or drive the sub down there with you.
Air burns faster the deeper you go. Nitrogen builds up — hover at 3–7 m before you surface or you'll get bent. Don't rocket upward. And when a shark starts circling, look it in the eye with your torch.