Hexen/Wastelands

In the area where you enter the level, find and follow the passage to an area overlooking a small canyon. A very important thing to note right off: nearby you'll see a small patch of dirt where it looks like the ground has been disturbed. Avoid standing on these: a huge spike here will intermittently stab up out of the ground, and it's instant death if you get caught by it. There are many of these throughout the level.

First half
This level is mostly divided into two parts. The first part consists of small valleys and canyons interconnected by a complex of mine tunnels. You'll find it helpful to consult the automap, because the many similar areas can make things confusing. First off, thoroughly explore the mines and canyons, clearing out the enemies as you do. Things to note:
 * You'll find three small places where the rock is gray instead of brown. When you've killed most of the Ettins wandering around, doorways in these three areas will open, leading to the other half of the level. This is described below.
 * In a small canyon is what looks like a door or barrier blocking a tunnel
 * In one tunnel is a wide window looking down into a large cavern with a lava pool and a structure
 * You'll find an outdoor area that's more vegetative than desert. In this area is a door or panel of sorts that needs the Cave Key (but only seems to be covering the small structure), and a teleporter blocked off by bars. There's armor behind the structure.

Horn Key
Your initial objective is to find the Horn Key, which you'll need in the other two levels. Along the south end of the level is a mine tunnel that's much longer than any of the others. To get there from the canyon near where you entered the level, take the tunnel that was to your left, and go right at the junction. You'll find the vegetative side area mentioned above on your right. Clear out the area if you want, then continue up the tunnel, looking for a short passage to the left with an unmarked panel at the end. The panel is a revolving door of sorts that spins when activated. Go inside, and up to an outdoor area with two muck pools and a long area filled with lava. Follow the narrow pathway over the lava to the far end, where you'll find the Horn Key. When you pick it up, the pathway will disintegrate somewhat into stepping-stones, but they're close together and you can run over them without trouble. If you fall in the lava, look for and pull the switch down by the lava next to the entrance to the area. This lowers a lift, allowing you to get out.

Second half
If this is your first visit, your task is completed, but it's a good idea to get the rest of the level that's accessible opened up. The three gray-stone doorways to the second part of the level should now be open, if you cleared out the enemies. The second part consists of a network of deep slot canyons made of gray stone. Many Centaurs are in here. When most of them are killed, the walls of some of the canyons will lower, revealing a big swamp. Watch out for gasball-shooting Stalkers in here. At the far end of the swamp is a doubling-back stairway leading to a door that needs the Swamp Key.

Elsewhere in the slot-canyon complex you'll find a low meandering tunnel leading to a small room that's actually a deep pit--be extra careful here. In front of the pit is what looks like a gold pig: this is a Porkalator. It turns enemies into pigs which are easily killed. (This is comparable in concept to the Morph Ovum in the game Heretic.) Also within the complex are two routes leading up to the big ledges overlooking two of the canyons in the first half of the level. (One is above the canyon near where you entered the level.) On one is what looks like a silver and purple cup: this is a Krater of Might, which fills up your store of mana. On the other you'll find Boots of Speed.

If you have the Cave Key and/or Swamp Key, you can complete the applicable side areas next.

Cave Key side area
Go to the vegetative side area at the south end of the level, and open the door/panel that needs the Cave Key. A portal to the Caves of Circe is behind it. Nevermind it, and instead go to the teleporter which is now unblocked. Before entering it, save your game: the mechanics in the next area can be problematic and there's a risk of being unable to complete the level. You may need to reload your game and redo it.

The teleporter goes to the big cavern with the lava pool and structure. Kill the Afrits in here: when you do, a magic bridge up to the structure will form. If the Afrits are near the structure, try to lure them away before killing them. If any of them are in the spots where the magic bridge segments will be, there will be a gap in the bridge you may not be able to get across. If this happens and you can't get to the structure, reload your game and try again.

Up on the structure you'll find this area's puzzle-piece lever, and a Mystic Urn. After pulling it, look for a passage in the cavern leading up. This is the tunnel with the barrier; the barrier is opened from the inside.

Swamp Key side area
Go to the swamp, open the Swamp-Key door and pull the switch inside. The torches will light. When you go outside, you'll see that a massive area to the left past the swamp has opened. (You may have noticed a big blank area on the automap here. The inner wall of the long curving slot canyon has lowered.) In here, a stairway leads up to two big covered areas to each side, a pool ahead, and a door beyond. After clearing out all the enemies, open and enter the door (try activating one half or the other rather than in the center, if it doesn't want to open). Inside is a tall room with a portal to Darkmere. Look behind the portal and pull the puzzle-piece lever on the wall.