Vale Cave

Vale Cave is an optional dungeon-style cave location accessible from within the town of Vale in Golden Sun. It can only be entered by using the Lift Psynergy, found later in the portion of the game that takes place on Angara, on the boulder in the middle of the fence near Kraden's independent cottage. It is quite short and has no relevance to the main plot, and has no background information. It contains the Halt Gem utility Psynergy item, as well as the Jupiter Djinni Kite.

Walkthrough
Upon entering the cave, you'll see that there are paths leading north and northeast, but both of these lead to dead-ends; instead, you're supposed to jump onto the right pillar of the circular series of six wooden pillars in the water, use Reveal to show that there is a hidden seventh pillar in the center of the formation, and hop left. Follow the subsequent path up to the next watery room, which has two tall wooden crates; first, use Move on the crate to your immediate right and shift it left one space so it falls into the water, and now you can access the doorway to the immediate southeast, where you find a chest containing a Nut. Return and use Move to move the left crate two spaces right so that it also falls into the water, hop up onto the vertical rolling log in the water, and ride it to the right end of the room. Enter the northeast doorway.

In a room that branches left and right, take the left fork, and you'll be linearly led out of the screen's southeast exit. In the next room, push the right vertical log left into the water below, then hop over to the left vertical log and push it right into the water below. Slide down the wall slide, then roll the horizontal log up so that it rolls along the two logs to settle just short of the open gap to the other side; hop through this gap and go down the exit to the left.

You will emerge in a room where a Jupiter Djinni is immediately visible. Go up and climb to a chest containing the Halt Gem utility Psynergy item, equip it on an Adept, then go down to scare the Djinni to the area below. Slide down after it, and you'll find that it will evade your attempts to capture it by mirroring your movements around the three rocks it keeps between you and it. While standing directly opposite the Djinni at the center of the three rocks, use your new Halt Psynergy to keep it in place so you can walk around to it and collect it without a fight. Vale Cave is now already complete, so now go through the south exit and go into the south exit below that to return to Vale.

Collectibles
Kite: It flees whenever you approach it, but you can stop it with the newly-acquired Halt Psynergy.

Nut: In a chest to the upper left of the room with both the Halt Gem and the Jupiter Djinn.

Halt Gem: In a chest at the end of the puzzle.