Level by Osvaldo
Walkthrough by Phil Lambeth, assisted by Doggett TV's video walk
Hop down into the passage and shoot the grate blocking the exit. Shoot two MPs in the room below. One of them drops a small medipack. The grate in the corner window can be shattered. Step forward for SECRET #1 and hop down into the lower passage. Crawl underneath the laser, pick up the SHOTGUN, shotgun ammo, flares and a small medipack at the far end and return past the laser to the previous room.
Push the wall button to open the adjacent door and follow to the next room. Avoid the deadly wire-protected portions of the floor that alert the sentry gun mounted in the far corner if triggered (only the grated areas are safe) and jump your way to the other side, ignoring for now the passage to your left. Turn the corner and shoot an MP. When you reach the wall an alarm is triggered and a guard appears. Turn right and follow the passage to a ramp leading downward. Go there and meet a dog and a guard. Note the wall receptacle, pick up the dropped shotgun ammo and wait for two MPs to approach from the top of the ramp.
Go there, turn right and ignore for now the ramp leading upward. Push the wall button to open the door and avoid shooting the friendly inmate inside. Enter the crawl space and wade quickly through the muddy water until you emerge and trigger SECRET #2. Pull up left for flares, shotgun ammo and a large medipack. Go back the way you came, using the health crystal on the way back, and now go up that ramp.
Turn left at the corner and engage an MP in the next room. If you can entice the inmate to follow you, he'll deal with the MP so you don't have to. Pick up the dropped shotgun ammo and note the green lasers crisscrossing the room at various levels. Locate and push two buttons in the central structure to open doors in the far wall, then locate and shoot the grated panel with the different texture. Pull up inside and follow to a lower passage protected by a green laser and a red laser.
Hop down, pull up over the block when the red laser moves away and jump forward for SECRET #3. Jump into the water and don't worry about the friendly orcas. Grab the DESERT EAGLE, the small medipack and the desert eagle ammo, go back the way you came while avoiding the red laser (the green laser doesn't pose a problem), and hop down left into the previous room. Jump over the lower green laser and go through the opened doors toward the next room but don't enter.
The room is protected not only by green lasers but by a sentry gun mounted in the far corner. Stand left, take one step inside the room, turn with your back to the locker and stand jump over the green laser (which will alert the sentry gun if you trigger it) to grab the crate. Pull up and go to the other corner, take a running jump over the green laser toward the next crate and pull up onto it to face the still quiescent sentry gun. Hop down the other side to alert an MP (if you were lucky the inmate rushed into the room ahead of you and dealt with him). Pick up the small medipack he dropped and the nearby KEY CARD 1. Go back the same way you came to avoid the green lasers and exit this room.
In the next room hop over the lower green laser and backtrack all the way to that room where you had to jump over several trip wires and enter the passage you ignored earlier. Use the Key Card 1 to open the door and go in to release another friendly inmate and attract an MP. Wait for the former to kill the latter (the first inmate may show up to join in the fun) and climb over the block into the room. Shoot the grate and follow around the corner to a lower passage guarded by a red laser. Hop down, turn around and push the button. Crawl underneath the laser to the other side and pull up left.
Go through the crawl space and shoot the MP in the next room. Go to the far wall underneath a laser, pull up left onto the crate and pick up the BLUE FUSE. Hop down and deal with three MPs who have appeared down below. They're more interested in the inmates (assuming they've already arrived on the scene) than they are in you, so you can shoot them in the back at your leisure. When they're dead, go quickly through the crawl space before yet another MP appears. Return to the hallway with the ramps and go down the first one to your right. An MP is waiting for you, but a friendly inmate should be on the scene as well. Use the Blue Fuse to open the door. Follow around to a ramp leading down to a room where another MP is waiting.
In the far right corner is a closed door to be opened with another fuse. Go past the right side of the ramp to a passage leading to a new room protected by lasers. Hop over the lower laser near the entrance, turn right and shoot the grate. Hop up into the passage and turn left at the corner to find a stationary and two moving red laser traps. Hop over the stationary laser, wait for the lower laser to move away from you, jump over it as it returns and pull up at the other end for SECRET #4. Pick up the shotgun ammo, desert eagle ammo and a large medipack, and return.
Hop down into the previous room, crawl toward the opening in the opposite corner, jump over the final low laser and follow the passage to the next room filled with crates. Run around to attract the attention of two MPs and locate the wall switch on the back side of the central stack of crates near the entrance. Pull it down to open a trap door in the far corner behind you. Go there, drop down and follow the lower passage to another room with crates. Go around the crates to alert an MP, pick up the small medipack he drops and find the YELLOW FUSE in a nearby alcove.
Go back up to the larger room with crates and deal with two MPs who have appeared. Exit this room, hop over the laser as you enter the next room and crawl to the opposite corner to exit. Follow the passage to the small room with the ramp and go to the far corner to find the receptacle for the Yellow Fuse.
Open the door and come to a room crisscrossed with multiple lasers. Climb up onto the crate to your left and take a running jump onto the left side of the next crate. Turn to face the third crate and carefully take a curved running jump to land just in front of it. Crawl to the left side of the opening in the far wall, stand up and run forward toward the next room. The door closes behind you, blocking the laser that was protecting this passage.
Shoot the approaching guard, pick up his shotgun ammo and enter the next room to face a panel of three buttons. There are also three closed doors, but you need to save the door in the back wall for last.
Push the first and third buttons to open the door on your left. Follow the passage to a room with moving red lasers in the trenches and trip wires on the ledges. Pick up the large medipack at your feet, stay close to the wall on your right and take a running swan dive over the first ledge. Step back and stand jump over the second ledge. Continue in like manner until you reach the far ledge, turn left and run to the other end to pick up the BLUE FUSE. The video walk indicates that if you made it across without tripping any of the wires, they disappear, making your return trip much easier. However, I could never accomplish this and had to use medipacks to get over and back.
Return to the button room, push the first button again and then all three buttons, and the door to your right opens. Follow around to another room with ledges and trenches, pick up the small medipack and find that in this room it's impossible to jump unscathed over the trip wires. Stand under the nearest ceiling channel, climb up onto the ledge, wait until the laser starts moving away, jump up to grab the ceiling and monkey swing forward to drop down in the trench before the laser returns. Turn to your right, take an angled running jump over the trip wires in the trench, select the ceiling channel with the overhead monkey bars and proceed in like manner, timing the red lasers, until you reach the far side of the room. Drop down, run to your right and pick up the YELLOW FUSE. Go back the same way you got here and return to the button room.
When the button on the left is red and the other two are green, the door in the back wall should open. Proceed to a small room with receptacles for your two fuses. Insert them both to open the exit doors, and out pop two guards. Enter and pick up the blue artifact to end the level.