Terraniux

Now the biowaste water has drained away. Proceed along the corridor loop until you see the computer console. Above the console is a glittering Force Field. This protects the control room that manages the flow of waste. Walk up and read the console, then drop down and kill the Mercenary on the bottom floor. Walk underneath the force field area and up to the huge octagonal door. It opens revealing Sliths, retreat and fire, enter the door only when they are all dead. You’re now in a big loop of corridor dotted with ramps and octagonal exits. Walk in either direction and examine doors as you pass them. Most are sealed, one however is open. Enter and you are inside one of the three biowaste containment chambers. Kill the Mercenaries you meet and get your bearings.

Ride a lift up to the top of this room. It’s irregularly shaped and features a large glowing button. Press it and go to the opposite side of the room. An exit leads to a central walkway. The walkway connects the three biowaste containment chambers, and at the centre is a lift and biowaste waterfalls.

Proceed around the walkway and investigate the other two waste containment chambers, they’re more or less identical, each with Mercenaries and a button to press.

When you are done, return to Chamber A, a computer screen near the exit identifies it as A and it will be full of biowaste. Find a side door in chamber A and go through it. Beyond is Lift 1. Take it upstairs to a network of four greenhouses. Explore this area thoroughly for Mercenaries and pick-ups.

Next look for a blank metal wall at the edge of Greenhouse C, as you approach it drops and serves as a lift, allowing you to enter a new room. Kill the Mercenary there and note the strip of glowing alien characters on the wall. Jump into the biowaste and take the tunnel that leads under these characters. You’ll emerge in a large room with a Mercenary.