In the final battle, the Mermi-Crew must come together -- or risk losing the ocean as they know it forever. 

A cruel deception forces Astra to devise a risky plan to save the Mermicornos from being further torn apart. 

As the Mermi-Crew readies to face Ika again, they're met with a surprise that may help their mission ... or cause them to fail entirely. 

After discovering his creative side, Sawtooth must decide if he's a Hench-Shark or a Mermicorno. 

Astra adopts a laid-back persona to impress Rip Tide and Sunsprite. Meanwhile, Squishella's jealousy leads to magical mayhem. 

The Mermi-Crew set out in search of Valentina ... but soon realize that while finding her is easy, getting her to leave is hard. 

The Mermicornos finally make it to the Mermicorno Kingdom ... but new revelations threaten to change the Mermi-Crew forever. 

When the Mermicornos find a community of fish being bullied, Gwen takes matters into her own hooves. 

After discovering she's part of a secret society of turtles, Kameko starts to wonder where she belongs when she doesn't fit in. 

While Ika begins training Dark Pearl, Squishella enters a talent show -- but her determination to win has monstrous consequences. 

Kameko sets out to find her dad, while Nautique recounts his life post-Starfall with Squishella. 

To obtain a relic that could lead to the Mermicorno Kingdom, Astra and Gwen journey into a secret vault under the Pearl Palace. 

As Astra struggles with the events of the Lunar Eclipse, Sawtooth wrestles over new insight from his past.