Quake II/Grid Control

Level objective
The primary objective for this level is to destroy the security grid protecting the industrial region, with a secondary objective to locate and destroy the Grid Control Computer.

Proceed up the illuminated stairs directly in front of you. On the platform on either side you'll see a Jacket Armor and a Grenade Launcher in the midst of four large columns with pulsing, blue laser beams. The items are worth getting, but the beams are too low to crawl underneath without taking severe damage. Quick-save and time your dash into and out of the laser rings.

Walk through the door to the west. As you stand in the "T" intersection, look down the gallery on either side of you. To the north you'll see a red wall button that operates force fields in the portals at both ends of the gallery. You can toggle the force fields on and off, from there, but as soon as you take a couple of steps past either portal to the inner gallery, the force fields are activated and you can't go back; there is no corresponding button beyond that to deactivate the fields.

There are two lift platforms at the opposite end of the room, one in the southwest corner, the other in the northwest corner. Your objective is to get to the southwest lift, but you need to get past arrays of scanning and pulsing blue laser beams. There is a column in the center of the area surrounded by deadly red laser beams. You can go down the outer gallery, timing short dashes between the pulsing beams, or — more easily — crawl under the diagonally-scanning steady beams in the inner area, staying close to the wall.

Step on the southwest lift and ride to the platform above. The platform contains a square structure with high walls in the center, and there is a high wall all around, forming a closed path around it. There are two Tanks standing guard, one on the west side, the other out of view on the east side. Stand on the edge of the lift opening, just out of sight of the west Tank, and fire on him with the Railgun. If you do it right, he'll say put and just take the hits. Four shots should do it. As soon as he's down, the east Tank comes around the corner. Move onto the platform and use the corner of the center structure as cover to fire on him with the Railgun. At the greater range, it typically takes five shots to knock him out.

As soon as the Tanks are eliminated, the floor starts shaking violently and there are sounds of explosions. The walls on all four sides of the central structure crumble, leaving just the "L"-shaped corner supports. There are three Berserkers hiding in those corners, except you can't see them and they can't see you if you're at the southwest corner. The rumbling, squeaking sound is from an enemy not described in the mission briefing manual — a cyborg mounted on a tank chassis with tracks, armed with a rocket launcher, chaingun and lasers — a sort of "Super Tank" or "Tank Boss". Although his weapons pack a severe punch, he's slow, and you can use the four columns for cover while you take pot-shots with any of your more powerful weapons. Grenades, Railgun slugs and HyperBlaster shots work well. Weapons that take more time to shoot, such as the Chaingun, are not as useful, as they put you in jeopardy for additional time. You might also consider taking the Berserkers and Super Tank out with help from a Quad Damage.

Once the Super Tank has been destroyed, head to the middle of the floor where there's an opening in the center of a square marked by red and black diagonal stripes. Get on the ladder and climb down the shaft. Be careful to stay on the ladder, because the drop is long and will cause damage if you lose your grip.

Once you have climbed down the Grid Control Computer access shaft, here are no more enemies to eliminate in this area. Proceed west along the tunnel until you encounter a vertical structure with blue beams of light in it. This is the Grid Control Computer. It is invulnerable as long as the blue beams surround it. Step onto the small, circular lift platform just west of it and ride to the platform above, then walk around to the east of the machine. Press the button in the pedestal to raise a shielding cylinder, exposing the blue, lozenge-shaped computer core. Blue laser beams sweep the area, but as long as you stay at the pedestal, you are safe. Shoot the core with your Blaster to destroy it. You're done with the Jail Area Unit. A brief cut-scene is played as you proceed to Mines Unit.

Secrets
This level has no secrets.