Randi and his comrades have barely toppled Elinee when Luka calls Randi back to the Water Palace. Popoi and Primm agree to join him as there is little else to do; the former's memory has yet to be restored, and the latter's search for Major Dyluck is to pick up elsewhere.
When the three return, Luka informs them that Undine's seal over the palace is fading. Further, Luka senses that the guardian spirit may be in peril. She tells the party that Undine lives in a grotto to the east and that they can find her there.
The party travels east and finds the area teeming with Iffish. Advancing deeper, they spot a strange egg, from which a tonpole emerges. It feeds off the energy of the Mana weapons and becomes a biting lizard. Though boxed in, the trio defeats the creature. Further back, they locate Undine. She thanks the heroes for saving her, and in return grants Popoi and Primm her powers. Though Randi cannot use magic, Undine is able to give him the eighth and final Mana weapon, the javelin.