Warning! Spoilers ahead!
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• The first secret area is in the drain pipe above the slashable grate.
• Take one of the transport platforms up to the top level and find the reactor at the center. There is a control switch on both sides of the reactor. Press a switch once to deflect the power beam to one side, again to deflect it to the other, and a third time to restore normal reactor operation.
• On one end of the upper area there is a catwalk leading to the main laser's targeting system power switch. Find it and turn it on.
• On the other end of the top area, you'll find a magnetically sealed chamber with a hexagonal beam guide protruding from it. Be sure the reactor is in the normal operation mode and press the switch on the left front side of the chamber. The bomb-pumped laser will have no problem knocking that patrolling TIE bomber right out of the sky (Objective 1)
• The small chamber above the center of the reactor is a secret area. On the side of the reactor away from the magnetically sealed chamber there is a secret area in the rafters above the main laser's lateral control fields.
• Before leaving the top level, be sure to set a reactor switch so that it's NOT operating normally. (You should see a message about reduced power output.)
• Take one of the transport platforms back down to the main level. At the center of each of the four transport tubes is a pair of switches that will cause floor panels to open. Below the floor panels of each transport tube you'll find a power relay for the field sealing the large doorways. The order in which you find and slash'em is not important but here are some tips for each one:
  • Kell dragon area - if you stand in the center chamber out of the water you can find a spot where they're in range of your saber but you're outside the range of their bites. After you slash the power relay look out! One side or the other will be electrified. It's best to clean up the Kell dragons first, find any power-ups that might be about and slash the relay last. There is a secret area in the ledge above one of the Kell dragon pits.
  • Stormtrooper areas - These two areas are straight forward. Clean up the stormies, collect the power-ups, slash the relay and get out. Be wary of electrical malfunctions! In one of these two areas someone has the red key so be sure to search each one of them.
  • Dark descent - drop down from platform to platform until you get to the brightly lit area at the bottom. You won't have as much trouble finding the relay as you will getting out of there once the power droids turn nasty, but you can do it - use the Force. There is a secret area midway out along the uppermost platform.
• Once you have dropped the seal on any of the main doors you have to deactivate a power switch that you'll find somewhere on the other side. You can either activate, blast, or slash 'em.
  • Reeyes area - the power switch is on the elevated platform to your right as you enter this area.
  • Small bunker - the power switch is low on the wall in the far left corner of the bunker.
  • Data processing center - work your way around, under, over or through all that equipment until you come to the small red key door at the end. The power switch is just on the other side of the door to your right.
  • Field Test Chamber - The corridor is recognizable by the light brown trim and a large grey arch at one end. The power switch is in a room down a corridor on your left just before you reach the arch.
• Once you have dealt with the fourth power switch and Objective 2 is accomplished return to the Field Test Chamber. There is a slashable grate on one leg of the arch. Hop inside the duct and follow it to the center of the complex.
• Find the control area in the very center. Pick up the data encryption rod to accomplish Objective 3. There are four control switches set in the floor. Deactivate all four of them (any order) to disable the bomb-pumped laser's lateral control fields.
• Press the switch on the side of the raised cylindrical platform. Get on the platform and keep jumping till you reach the inside of the anti-gravity tube. You can do it. Once you're back on the top floor slash the grate that was blocked by the main laser's lateral control fields. Make your way down the tunnel back to the Crow to accomplish Objective 4 and end the level.