Secret of Mana/The Underground Palace

Water Palace
Once you arrive at the teleport from the Mysterious Forest, head right and run up immediately to return to the Water Palace. When you reach Luka, she will restore any lost health. Then she will mentiont that the seal on the Water Temple is weakening. She instructs you to visit the cave to the east of the palace.

Undine's Cave
When you exit the palace, climb down the stairs, but remain in the water and head to the right. There you will find a small pond with a cave in the back. This area is protected by three Iffish. You are not required to fight them, but it's still a good idea to collect more experience points.

When you're ready, duck inside the cave. Inside, you'll find another body of water. Once again, it is protected by three Iffish, and once again, defeating them is optional. Make sure you have relatively high health before proceeding to the next room. If necessary, you should return to Luka and have her heal you back up before challenging the creature in the room above.

When you arrive in the next room, you'll see an egg with a heart on it. The egg will hatch, and a Tonpole will appear. The Tonpole itself is not too difficult of an enemy to fight. It hops around and attempts to damage your players by crashing into them. However, when it takes enough damage, it will not be destroyed. Rather, it will evolve into a Biting Lizard.

The Biting Lizard is a much bigger threat. It has the ability to use Cure Water on itself to heal its wounds, and it will stick out its tongue in an effort to grab one of you, chew you up, and spit you out for great damage. For this reason, it is necessary to battle to Biting Lizard much more carefully. It is possible to get the Lizard into a place where it can do less damage if you carefully maneuver it closer to one of the walls, or into the passage that leads back to the previous room. Never the less, it's a good idea to keep a lot of healing supplies on hand.

When you defeat the Biting Lizard, you will obtain the Glove orb, and the door to the room above will open. Head through the door and the Water Spirit Undine will appear before you. She will gift the Girl and the Sprite with two forms of magic. The Girl can cast defensive magic that heals damage and restores state. The Sprite can cast offensive magic that damages enemies or changes their status. When asked about the Boy, Undine states that the Mana Sword, once repaired, will be more powerful than any magic. In the mean time, elemental status can be cast on any of the mana weapons. Before you leave, Undine will also present you with the final mana weapon: the Pole Dart.

With your new found powers, it's time to return to Luka in the Water Palace. On the way out, practice casting magic on Iffish. Now that you have magic, you'll need to begin leveling it up, just like you have to level up your weapons, in order to make them more powerful. The more you cast magic, the more that element will earn experience until it advances to the next level. Take as many opportunities as you can find to cast magic. Upon returning to Luka, she will suggest that it is now time to visit the Underground Palace. You must now return to the Dwarf Village beneath Gaia's Navel.

Underground palace
The path to the underground palace is blocked, but can be opened with water magic. Return to the Dwarf village near Gaia's Navel, and enter the cavern opened by Tropicallo. Cast freeze on the crystal to open the palace. This cools the lava and opens the first door.

The underground palace has the five major rooms:


 * 1) In the first room, you will encounter goblins guarding a door.  Behind this door is the stairs, blocked by a large torch.  Head to the left and right to press the floor switches to remove the torch.
 * 2) The second room snakes to the left, and requires using the whip to swing across.
 * 3) A few goblins will guard a small room.
 * 4) This room is shaped like a "U", with Goblins and Chess Knights. The only exit is on the left.
 * 5) The final corridor before the stage contains a few goblins, before you climb up the stairs.

Once you climb the stairs, a cutscene will appear with Gnome blocking access. However, a monster approaches, causing the Gnome to flee.

Boss: Fire Gigas
Defeating the Fire Gigas will give you another Axe orb. Proceed north into the mana seed room, where you can learn earth magic and use the sword with the mana seed. Once this is complete, all monsters in the underground palace will disappear. Popoie's memory will return, and he will mention that he lived in the Upper Land forest and that you'll need to head there.

You can't do that yet. When you return to Luka, you will learn that Jema hasn't yet returned from Pandora. You will need to head there to rescue him.