After finding out more about where they are, Cless/Cress and the others meet Klarth/Claus and continue on their way.
Leave town, and go east across the bridge. Go north past the house in the mountains and you will reach a town. Buy a Pick-axe and Rope from the item store. You might want to buy Holy Bottles and Dark Bottles as well. Upgrade weapons and armor if you wish. You will get a Kite Shield and an Amber Cloak for free later, but you can buy them now if you prefer. The Warrior Sword is the most balanced weapon here.
If you haven't already, go back to Euclid and buy plenty of food. You will need it for the next part.
Leave town and go back to the house in the mountain pass. There is a chest (Thief's Mantle) behind the house. Talk to Bart. He will give you the Opal Ring. Equip it on Klarth/Claus. You can rest for free in Bart's house.
From Bart's house, exit to the north to enter the Long Valley. Check on the rocks in your path to break them with the Pick-axe. Keep going up, and when you see the wind blocking your path, walk to the right and talk to the Sylphs to fight them. Lightning Bolt works well against the blue ones, but you will need to use regular attacks on the pink ones.
After that fight, walk straight down to find a chest (Blue Ribbon), then continue north.
After the save point, go through the tornadoes to the right. From there, go up, and use the leftmost entrance to the cave.
Go up until the wind blows you to the right, toward a save point. Go to the right and up from the save point and get behind the hole, then check on the little wooden post to send a rope down. Climb down.
Follow the path, using the Pick-axe on the wall in your way. Go past the stairs for now, and go right and break the wall to find a chest (Spy Lens). Then go left and down the stairs. After breaking down the wall, walk left and go up the rope.
Before fighting the Sylphs, go down and left from the hole and exit the cave to find two chests. From right to left, they contain a Kite Shield and an Amber Cloak). Then go back in and walk up to the Sylphs to fight them. Don't use Lightning Bolt against them this time.
When they are gone, go to the right and up to an area you couldn't reach before because of the wind.
You will come to an area filled with Shoki/Miasma. Try to walk around the Shoki/Miasma to avoid getting injured too much from it. Make sure your food sack is filled.
Go to the right from the bubbling pool and break the wall with the Pick-axe. Drag the stone and use it to cover the bubbling pool.
Now walk to the right, past where you got the stone, and follow the path until you reach another hole where you can use your rope.
This next area is dangerous. If you encounter a Hell Lord, run. You can't beat it at your level. You might want to equip a Thief's Mantle to run away from Hell Lords more quickly. You can use Holy Bottles if you want to have fewer battles. Also, check your food sack often to make sure that there is still food in it. If you run out, you might want to exit the cave and get more food, because your health will keep going down.
From the save point, go down, right and up, and you will find a stone. Drag it as far down as you can, then as far left as you can, and finally, up. Cover the rift. Unfortunately, there is still another rift.
Go east, then north, back to where you got the stone, and go north up that path. Go right from the rift to find a chest (Talisman). Break the wall to the south to get the rock. Cover the rift.
Now leave this area the way you came in, up the rope.
Get the treasure above you (Rune Bottle), then go down to leave the cave.
Long Valley and Summit
Go to the upper right of the screen and into the next area. Follow the path to reach the Sylph.
Klarth/Claus can summon magical spirits that he has contracted with. Each spirit does a different kind of elemental or physical damage, which different enemies are weak to. Just as with Mint, you can turn off individual summons from Klarth/Claus's skill menu.
It is recommended to set Klarth/Claus's tactic to "Don't Call Spirits" unless you are in a boss battle, to conserve his TP.
His tactics are Call Many Spirits, Call Spirits, Conserve TP, and Don't Call Spirits.
Go back the way you came. Go south from the cave entrance and you will find a chest (Apple Gummy) tucked in a corner. Then go west as far as you can to find a chest (Charm Bottle) that you couldn't reach before because of the Sylphs' wind.
Now go back and talk to Bart. Rest in his house if you wish. Your next destination is the tree in the Spirit Forest south of Beladum.
You can stock up in Harmel and/or Euclid on the way to Beladum.
Go through Beladum to the Spirit Forest. Go south to the water, then east, then north, and check on the tree to talk to Martel.
When she's done, go north, through Beladum, then through the mountain pass.
After you go to the town north of Bart's house, you won't be able to rest in his house anymore.