Misdirection
The tunnel exit that leads to the hollow land of the Water Elemental realm now appeared like a busted tube end. The merman army standing at the back could still feel the faint tremors from the previous explosion of light.
Truly knowledge is a deadly weapon, if not for Danna stumbling about a book that mentioned the Shadow creatures from the realm of Darkness, she would probably have gone to a state of panic a while ago.
But now, with knowledge about the weird nature and abilities of the Shadows, she is just the perfect commander for this battle.
The two younger mermaid princess has already moved to evacuate their people back on the golden cave. Considering that they are fighting powerful creatures that are extremely advantageous with shady places, the golden cave just happens to provide a perfect form of shelter.