After defeating Master Belch, the zombies leave Threed, allowing you to go east to Dusty Dunes Desert.
Return to Threed
Go back to Threed through the secret passage between Grapefruit Falls and the Threed Graveyard.
The Insignificant Item
If you didn't get the Insignificant Item in the Threed hospital before, go upstairs in the hospital, enter the first room, and check the drawers to find it. You can take it to the Twoson Hospital and use the Insignificant item on one of the patients in the hospital rooms to get a Magic Truffle, which restores 80PP. Drop this item off with Escargot Express so you can use it later in the game.
Go through the Eastern Tunnel
Now that the ghosts are gone, you can use the eastern tunnel to reach the next area. It is a long walk, so you might want to take a bus. Check the bus stop sign across the street from the Threed Hotel
Once you go far enough, you will encounter a traffic jam. You will need to wander through the desert on foot to reach your destination.
Walk through the Desert
Go to the drug store and upgrade your equipment, rest at the inn (talk to the guy on the bottom-left), then stock up on supplies. The walk through the desert can be difficult. As you walk through the desert, there is a random chance that a member of your party will get sunstroke. If someone has sunstroke, the screen will flash red occasionally. Sunstroke will steadily reduce HP by a small amount until cured. Use any Healing spell to cure it, or buy wet towels at the drug store, and use them to cure sunstroke. You might also want to get food, and items to cure poison, in case you run out of PP.
Crossing the Desert
To enter the main desert area, go north from the drug store. You can purchase items from the military guy if you wish.
There are eight items that you can find in the desert. You can look for them now, or come back later when you have leveled up more. If you do want to get them now, start by going straight north from the drug store until you find a gift box near the water. It contains a Double Burger.
Then go northeast along the water's edge, and talk to the black dot in the sand. This is the Black Sesame Seed. The Photo Man will take your picture when you talk to it.
Go northeast from the Black Sesame Seed and open the gift box to get a Cup of Lifenoodles.
Then go southeast from there, then when you see a cactus, go south to find an oasis. Open the chest there to get a Skip Sandwich DX.
Then go southeast until you reach the edge of the lighter sand. Go east along the edge between the lighter sand and the darker sand. Eventually, you will find a white dot. This is the White Sesame Seed. Talk to it. (You can go northwest to talk to the Black Sesame Seed again. It says something different after you talk to the White Sesame Seed. But it's a long walk.)
Go east from the White Sesame Seed and open the chest to get a Big Bottle Rocket. Go east from here to find a house where you can stay the night and use a telephone. Talk to the miner outside and give him some food. If you don't give him food now, you will have to come back and give him some food at some point.
After you are done at the house, go west to the gift box that you opened a moment ago. Then go north from there and you will find some bones that you can talk to. Continue going north and check on the sparkle to get a Contact Lens. Then go north and open the gift box to get a Double Burger.
Then go east along the water and open the gift box to get a PSI Caramel.
Then keep going along the water to find a gift box that contains a Sudden Guts Pill.
At this point, if you followed the instructions above, you have found all of the items in the desert. Just go south from here along the water to find the tunnel to Fourside. Before you go east through the tunnel, you might want to go west along the road. You can talk to the Slot Machine Brothers and check on the machine near them to play the slot machine, with a chance to win a PSI Caramel, a Chick, a Can of fruit juice, or a Skip Sandwich.
Then keep going west from the Slot Machine Brothers and go north of the "Desert" sign to find a gift box. It contains $1000.
Then you can either keep going west to the drug store and check on the bus sign across the street to go east to Fourside, or you can just walk east through the tunnel to reach Fourside. If you walk, be sure to stand on the northeast corner of the bridge if you want the Photo Man to take your picture.