Trident Cave

Trident Cave is a cave above the Moon Pool on Mako Island. It has a secret entrance near the volcano that opens up during the Full Moon, or when the moon rings are used on it.

A pathway leads to a larger room that has a circular carving, with a trident head in the middle. When a Merman touches it, the circle transforms into a watery portal, leading to deep depths of the ocean where the Trident is located and where the first mermaids who ever existed hid the Trident, hoping it would never to be found -- until Zac did when him and Lyla were trapped in the Trident cave.

If a land boy touches it during a full moon, he sinks through the ground and into the Moon Pool.