Map 3 The Necropolis

Grab the grenade launcher ahead, then explode the three zombies waiting around the corner. Kill the ogre in the corner of the room, then destroy the caged ogre by aiming slightly high of it while you stand out of reach on the platform opposite. Go down the stairs to your right and bounce a couple of grenades around the corner to take out another ogre. Pick up the double-barrelled shotgun. Walk over to the bridge and drop a couple more grenades on the zombies in the pit below. Jump into the pit and find the secret area behind the nails, you may need to shoot the wall if the explosions didn't activate it. Get the goodies and find the lift back to the caged area the ogre was in earlier. Walk over the switch on the floor to open the cage, and pick up the armour. Go back down the stairs, but cross the bridge. Take the lift down and enter the cavern to right, explode more zombies, and head towards the water.

Beware that many zombies lurk throughout this area. Grab the gold key from the raised area in the water, keep heading for the wall opposite and you should start sinking, swim down and you'll find a secret cave containing the ring of shadows. Blast through the zombies and return back through the cavern. Take the lift up. Cross the bridge. As you go up the stairs approach slowly as another ogre is waiting for you, it has been released from another annex to the room. Kill it and you'll probably need to pick up the health in the room it was in.

Enter the room opposite, pick up the nail gun and shot the red button on the wall. The ceiling above will start to drop. Head through the corridor to a large room. Enter the room and retreat back up to the entrance. From this vantage point shoot the scrags and the ogre you encounter.

Enter the gold key door and kill the scrag you meet. Go to the bottom of the stairs and hug the wall, a spike will fly past you. Drop through the hole in the walkway and keep heading left exploding all the zombies you meet. Take the ramp opposite, grab the health and ammo, and return back down the ramp, and then take the first exit to the left. An ogre is on a platform behind you. Keep strafing left and right to avoid it's grenades. When you've dealt with it, jump up the steps from the wall to access the pentagram on the wall. Push the button to release zombies from four rooms below. Kill them and grab the goodies.

Open the wooden doors and look up, two ogres are on the platform above, avoid there grenades and explode any zombies wandering around. Kill the ogres. Killing the first ogre opens up some bars to the right of the doors you just opened, killing the other allows you to then get the yellow armour. Shoot the wall behind the armour to open a portal that will take you to another secret.

If you want to get 100% kills, don't go through the portal yet. Proceed along the corridor and open the remaining door. Press the pentagram button. The room turns into a giant lift to a floor above. Two fiends will attack you. Keep firing as you retreat in a circle, after you have killed one fiend, the other is easier, as you can dodge it's attacks and shoot it in the back. Leave through the gate for the next level or return to the yellow armour portal. Go through, you'll appear on the first ogres platform. Jump to the other platform. Turn right and shoot the wall to reveal another portal to the secret level. Run along the corridor because the floor collapses and enter the secret level.