- 1 Secret exit
- 2 Secrets
- 2.1 Secret 1: Top of the submarine
- 2.2 Secret 2: Turret alcove
- 2.3 Secret 3: Through the underwater cavern
- 2.4 Secret 4: Hidden door near the entrance
- 2.5 Secret 5: Toxic waste along the conveyor belts
- 2.6 Secret 6: Atomic Health inside the cylinder
- 2.7 Secret 7: Dark cave above the flooded chasm
- 2.8 Secrets 8-10: Series of cracks in the wall
- 2.9 Secret 11: Crawlspace beside the security monitor
- 2.10 Secret 12: Teleporters above the waterfalls
- 2.11 Secret 13: At the beginning of the sewage canal
- 2.12 Secret 14: Secret exit button
- 2.13 Other hidden compartments
- 3 Walkthrough
- 4 Development history
- 5 Screenshots
In the sewer tunnel at the end of the level, a crack can be found along the left-hand wall of the tunnel. Blowing through this crack will reveal Secret #14, which contains a secret exit to Launch Facility.
Secret 1: Top of the submarine
After escaping the submarine at the beginning of the level, climb atop the outside hull of the vessel. This will trigger a compartment to open inside the submarine. Although the secret has already been earned by climbing onto the submarine, the opened compartment can be found by emerging from the top of the water inside the sunken vessel.
Secret 2: Turret alcove
Outside the submarine at the beginning of the level, enter the cave above the water and follow this passage to a ledge with the Blue Access Card. On the left and right sides of this ledge, there are Turrets mounted inside alcoves in the canyon walls. After destroying both of them, jump from this ledge into the alcove on the right-hand side. Inside the alcove, open the wall on the left side to find a secret compartment.
Secret 3: Through the underwater cavern
Near the submarine, obtain the RPG beside the Blue Access Card and drop into the water below. Find the underwater cave in this area, and at the back of the cave, blast through a crack in the wall. Follow the opened cavern, and emerge from the water at the end of the passage to find a secret area.
Secret 4: Hidden door near the entrance
After using the Blue Access Card at the beginning of the level, the entrance hallway contains a hidden door along the right-hand wall, just past the first bend in the hallway. Opening the hidden door will lead to the windowed area full of Assault Troopers that could be seen from outside the facility.
Secret 5: Toxic waste along the conveyor belts
At one point along the network of conveyor belts, there is a narrow passage with red lighting. On the right-hand side, there is a small pool of toxic waste. Climb into the toxic waste, and open the wall on the left side to find a secret compartment with Chaingun Cannon ammo inside.
Secret 6: Atomic Health inside the cylinder
At the highest point along the network of conveyor belts, there is a control room with two cylindrical structures built into the wall. Beside the cylinders is a blue box on the wall. Using the blue box will cause the sides of the cylinders to open. Climb into the left cylinder, and jump up to find a secret ledge with an Atomic Health.
Secret 7: Dark cave above the flooded chasm
After being shrunk and flipping the switch to unlock the door, go through the doorway beside the shrinker beams and enter the water. Swim through the water to an outdoor canyon and emerge from the water. Climb to the highest point, where there is a jumpable chasm separating the two sides of the canyon. Instead of jumping across the chasm, jump into the dark cave adjacent to the chasm.
Secrets 8-10: Series of cracks in the wall
After jumping across the flooded chasm in the second outdoor area of the level, there is a control room with switches that change the water levels and open the underwater gate. Just outside this control room, there is a crack in the wall. Blasting through the crack will yield a secret area. However, this secret area contains another crack in the wall. Blasting through the crack will yield a second secret area with yet another crack in the wall. Blasting through this last crack will yield a third secret area that leads to the submarine at the beginning of the level.
Secret 11: Crawlspace beside the security monitor
Above the water in the second outdoor area of the level, go to the control room with switches and a security monitor. Use the wall between the security monitor and the red cylinder in the wall. This will open a secret crawlspace along the bottom of the wall.
Secret 12: Teleporters above the waterfalls
After passing through the rotating cylindrical gears, emerge from the water. Proceed into a narrow passage with a fast-moving water current that leads to a waterfall. Along this passage is a crack in the right-hand wall. Blasting through the crack will reveal a hidden room with a teleporter inside. Go through the teleporter to reach a secret area.
Secret 13: At the beginning of the sewage canal
After shooting the switch and jumping across the moving platforms near the end of the level, there is a sewage canal full of toxic waste. Before stepping into the toxic waste, look for a fan in the wall above the sewage canal. Shoot the fan, and climb a ledge along the right-hand wall to reach the opening behind the fan. Inside are two Atomic Healths.
Just before reaching the exit button at the very end of the level, there is a crack in the wall along the left-hand side of the sewage canal. Blasting through the crack will reveal a secret area containing a secret exit to Launch Facility.
The following hidden compartments are not counted as secrets:
- Above the water at the start of the level, go to the ledge with the Blue Access Card and RPG. Jump into the nook with the Turret on the left-hand side (facing the water). This is the nook directly across from Secret #2. The back-left wall of this nook can be opened to reveal a hidden compartment.
- Inside the secret compartment above, open the wall on the right-hand side. This will reveal another hidden compartment inside the hidden compartment.
- After swimming through the gears, before emerging from the water, there is an area with some darkened walls. Regarding one of them, it's possible to go through it and end up in a underwater room with some goodies.
- When you go down with the water flow in the area with the platforms, there is a button that moves the platforms that is revealed after you press a switch. While in the water, shoot the button from afar to move the platforms, go underwater, and you'll see a hidden cache behind the platforms. You have to be quick to get to the hidden cache or risk being crushed. You will get an RPG and a box rocket for RPG.
See Also: Duke Nukem 3D prototypes
There is footage of this level from one of the November 1995 prototypes.