Blood In the Water

You grip the machete heroically and go out to the bow to face the megalodon. It roars at you with its big jaws bearing sharp teeth and you almost make solids your pants. Pushing your fear side, you take a running leap onto its back and grab its dorsal fin. Shanking the back with the machete repeatedly, you try your best to do lethal damage to the megalodon. It eventually throws you off, but just as you were expecting to get eaten, the megalodon rolls on its back and dies.

Exhausted and relieved, you quickly swim back onto your ship, and that's when you notice that the bleeding attracted other sharks to the area and now they're gnawing on the remains of the megalodon.

Not sure whether to be happy or sad about this new development, you're just glad to be alive for now.