Children of the Deep

When Twilight chases a mysterious tablet to the bottom of the sea, what slumbers in the depths may rise again.

A mysterious artifact has surfaced on Equestria's coast: a relic from a realm long passed into legend and myth. Newly-crowned Princess Twilight Sparkle is tasked with leading the expedition to research its place of origin, but the lost city of Fathom may not be as quiet as they expected.