After you get the Hawk Eye in the Pyramid, you reach the southern desert.
Get the Key
Go northwest from the small pyramid and talk to the man with the spear to get the Key to the Tower. Then go north and talk to the man to upgrade your equipment. If you don't have enough money, there is an ATM nearby (see below), so you can come back here after you withdraw some cash. Get the French Fry Pan for Paula. The man also sells Multi-Bottle Rockets, which are even more powerful than Big Bottle Rockets. You can also get the Bazooka, which does the same damage as a Bomb, but you can reuse it as many times as you want.
The enemies that you will encounter here are the same as the ones you encountered south of Scaraba, with the addition of Marauder Octobot, which is weak to Fire, and a metallic enemy, so you can use Rust Promoter on it.
Go northwest to find a human-shaped tower. Prepare your ears for some weird music, then use the Key to the Tower to get in.
About Dungeon Man
There are monsters in here, but they are mostly weak, and there are several places to heal up for free, including a hospital just northwest of the entrance. The Lesser Mook can Diamondize you. This can be healed by the blue-haired healer in the hospital, Healing γ, Healing Ω, Cup of Lifenoodles, Horn of Life, and Secret Herb.
- Beautiful UFO (Weak to Brainshock. Metallic enemy. Use Rust Promoter.)
- Dali's Clock (Weak to Sleep.)
- Enraged Fire Plug (Weak to Freeze and Brainshock.)
- High-Class UFO (Weak to Fire and Brainshock. Metallic enemy. Use Rust Promoter. Starts with PSI Shield β)
- Lesser Mook (Weak to Fire and Sleep.)
- Marauder Octobot (Weak to Fire. Metallic enemy. Use Rust Promoter.)
- Mystical Record (Weak to Fire and Brainshock.)
- Robo-Pump (Metallic enemy. Use Rust Promoter.)
- Scalding Coffee Cup (Weak to Freeze.)
- Worthless Protoplasm (Weak to Fire, Freeze, Paralysis, and Brainshock.)
Explore Dungeon Man
Go north from the entrance, then go to the left. Check on the bench to recover your HP and PP. You can go into the hospital on the left if you need status ailments cured or mushrooms removed.
If you want to have room for all of the treasures that you can collect in Dungeon Man, make sure that there are ten free spaces in your inventory.
Then go east, and go north along the east wall to find a gift box that contains Molokheiya Soup.
Go south again, then go north up the slope. At the bench, go west to find a gift box that contains a Cup of Lifenoodles. Then go back to the bench and go south.
After the slope, go west and north. When the path splits, go south. Open the gift box near the sign to get $5. Go up the slope nearby and when the path splits, go to the right to get a Snake. Then go north to find a Super Plush Bear.
Go back the way you came until you have gone down the slope. Then go west and north. You find four ropes. Go up the third rope. In the next area, when the path splits, you can optionally go south to find a Good Night Bench. Otherwise, west at the split to find a gift box that contains $10. Then go east again until you reach the wall.
You can optionally go southwest to read a sign. If you went to the sign, go northeast again, until you are up against the east wall. Go south until you reach the south wall, then go west. When the path splits, there is a dead end with a sign if you go to the west, so go north at the split. Climb up the rope, then go south to get a Pizza. Then go north into the area to the left of the rope to get a Sudden Guts Pill. Then go farther north to find a PSI Caramel. Then go up the rope south of that gift box.
Then go east, and from there, go as far south as you can go. Then go west to get a Wet Towel. Go back east, then go up to where the path splits, and go west. Go up the rope at the end.
Go north and talk to Brick Road. Then go south and drop down the hole that you find. Keep going down the holes. Open the gift box on the way to get an IQ Capsule. Then drop down the nearby hole to reach the first floor. Go south to exit Dungeon Man.
Go with Dungeon Man
Dungeon Man will now be following you. He will help you during battle, and is very strong.
Go south. If you want the Photo Man to take your picture, walk to the right of the tree north of the pond that is south of where you first found Dungeon Man.
Then keep going south until Dungeon Man gets stuck in some trees.
Find a Way to Continue
Go east and talk to the man with the spear. Say Yes when he asks if you want to go to the Deep Darkness. He says that you need a submarine to reach the Deep Darkness. Go back into Dungeon Man.
You might want to withdraw cash from the ATM before you continue. Then make your way back up to Brick Road's face (the path is the same as before; see Explore Dungeon Man), and talk to him. He says to drop down the other hole on this floor. Go south, then east, to find that hole. Fall in, and keep falling through the holes you find. When there are no more holes, go east to get a Talisman Ribbon.
Then go west and follow the path until you reach Brick Road's collection. Use the Instant Revitalizing Device to heal up, then check on the yellow submarine. There will be a cutscene as you proceed to the Deep Darkness.