Mystic Ark/The Ark of Light

The door to Fruit World
Leave the island temple and walk west. Enter the windmill, and use the Ark of Power on the switch. Go back to the temple, enter the door on the left, then look closely the big squash.

Watermelon Town
Infuse the Ark of Power to one of the six figurines. Purchase equipment accordingly.

Dungeon: the foxhole
Travel east from Watermelon Town until you get to Gourd Bridge, across the dry river. In the northwest room, burn the leaf. Use the Ark of Power on the door to open it. Get the tofu from a prisoner, and put it on the fox altar to open the dungeon. The chests are trapped and optional, but the foxes inside provide good experience. Leave the dungeon to heal, then come back and continue.

BOSS: Metal Fox
Stronger than the previous foxes.

Gourd Bridge
Upgrade the equipment at the shops. Solve a puzzle to get a weapon for Meisia the Priestess.

Using the figurines
Get the Pineapple Seed Heart and the Grape Seed Heart from the item merchant. The figurines are in the temple, in the boxes near the big squash. Go back to fruit world, cross the dried river at Gourd Bridge, then plant the seeds in two fertile soil areas on the North bank.

Before the dungeon
Go back to Watermelon town and speak to the Elder.

Dungeon: beetle forest
It is located west of Watermelon Town.

BOSS: Beetle
He's quite slow and not very strong, but he has good endurance.

Cramped Pineapple Town
The people in Watermelon Town moved here. No services nor shops yet.

Dungeon: Crow Forest
It is northwest of Pineapple Town.

Hearts & figurines: the little bird
When you get to the tree with the crow, talk to the tree and a spirit will tell what happened. Shake the tree to get a Hatchling Heart. Back on the island, a hatchling figurine is found outside the temple, near its northeast corner. Bring it back to the crow, then bring the Grape Seed back into its fertile soil.

Pineapple Town
The town got bigger, and it has an item shop now.

Dungeon: mountain cave
Get some fresh water at the spring, then walk back to Watermelon Town and one of the Couch Potatoes will join you. He'll move a rock and revive the river.

Grape Town
Thanks to the water, Grape Town is born and Pineapple town grew up to be a full city. When you talk to the elder in Pineapple Town you'll find out that Grape Town is invaded.

BOSS: Beetle again
Same boss as before. He'll drop the key to access the big tree.

Dungeon: Great Tree
It is located northeast of Pineapple Town. On the branches, you can climb the vines to get to upper levels.

BOSSES: King Beetle and Sly
Two battles in a row! When you defeat both, you'll win the Ark of Light.

The Ark of Light
Infuse the Ark of Light in a weapon to make it far stronger. It affects sharp weapons, but not bludgeon weapons (Priestess staves, Tetsujin fists, Grappler nunchakus).

Pineapple Town and Grape Town
Pineapple Town grew further after you defeated the beetles. Grape Town will grow only after you manage to leave the first town in the next world.

Secret mini-games
Examine one of the trees near the location where you got the little bird figurine. Infuse the Ark of Light in it to access a secret area with two mini-games.

Also, explore the cave on the southern beach. Use the Ark of Light on the fountain in order to open the door. Use the Ark of Light on the sword to access the figurine arena.