You begin outside in a very large and deep courtyard, most of which is taken up by a labyrinth made of high walls, much like a hedge maze. First, thoroughly explore the labyrinth and clear out the enemies. Along the outer wall of the courtyard, you'll find a side area leading down to the Blue Door. When you're finished, look along the walls making up the labyrinth for a section with gold symbols on it. Activate it and the section--a hidden lift--will lower. (It's the zigzag section of wall closest to the Blue Door.) Ride it up to gain access to the tops of the labyrinth walls, where there's a great deal of ammo and items. Get a running start to jump from section to section.
Main corridor and side rooms
Beyond the courtyard is a long meandering corridor that leads from southwest of the courtyard, around the courtyard, and to the northwest, with various side rooms along the route, most of which are closed. To gain access to the corridor, get a running start and jump over to one of the overlooking areas on the north or south sides of the courtyard. You can reach them easiest by jumping over next to the cauldron torches. Also, in the four corners of the courtyard, you'll see small overlooking areas that are in the dark with occasional flickering, with passages leading away. (You'll usually be fired on by Ophidians from them.) Sometime, jump over to the ones you can reach. When you reach the far end of the passage, activate the wall at the end and a door will open, connecting to the main corridor. Also, another door of the same style will open nearby across the corridor, allowing access to an outer side area along that side ("outer" meaning opposite the main corridor from the courtyard). These doors are rounded on the corridor side and have blue tapestries. The converse is also true: if you open a door from inside an outer side area, the door across the corridor to the nearest four-corners side area will also open. You can get to that one four-corners side area you couldn't reach from the labyrinth this way.
After accessing the main corridor by the means of your choice, explore it from end to end. At each end, beyond the general area of the courtyard, a long twisting stairway will lead down. At the bottom of one is the Yellow Door; at the other the Green Door. Opposite the courtyard you'll see two windows looking into side rooms full of Ophidians. Try using your Phoenix Rod on them: remember that they drop Flame Orbs worth five rounds and frequently at that, and you'll come out ahead and may replenish your stock even if you began the level without any. Those side areas are the ones accessed by opening the doors in the four-corners side areas, as described above. There's loads of ammo available, so be sure to explore all of them. Each also has Wings of Wrath: hold onto at least one of them, because there's a difficult area later that will be significantly easier if you can fly.
Your first main task so far has been to find the Yellow Key. Go to the midpoint of the main corridor, in the area overlooking the east side of the courtyard, and hit the switch here. Many doors along either side of the corridor in this general area will open. The doors were all sections of wall sticking out. The ones along the inner side go to a couple of small side rooms with enemies and items. Look for and go to the doors along the outer side of the corridor. In here is a long tall room with a platform partway up the wall spanning most of one side, on top of which is the Yellow Key. Jump over to the platform from the steps and collect the Yellow Key. When you step onto the platform, it will lower, opening a long compartment and releasing a bunch of Gargoyles.
Go to and open the Yellow Door. In here is a huge dark-paneled room with a bunch of lava columns flowing from the ceiling into small pools. After fighting the enemies, go to the low platform at the far side of the room and hit the switch on the column. The largest lava column in the center of the room will lower, releasing an Iron Lich. You'll find the Green Key on top of the lowered lava column. When you step onto the column, the remaining lava columns will lower, releasing some more enemies. The fun way to fight the Ophidians is try and maneuver them into a group and then let them have it with the Phoenix Rod. When you've defeated them however you choose, look on the lowered lava columns for some more items.
Lava, columns and quadrants
Go to and enter the Green Door. This room is where Wings of Wrath will simplify things a lot. In here is a big and deep octagonal lava-covered room, with a ledge around the perimeter and high walkways dividing the room into four quadrants. In each quadrant is a big lava column flowing down, surrounded by a shield that intermittently raises and lowers, plus there's a fifth column of dark metal in the center of the room where the walkways cross.
The room is crowded with Disciples of D'Sparil. Fight them individually as much as possible, and if you take a pummeling there's health all over the place in here. Go to and activate the center column. It'll open, with the Blue Key inside. Also, the lava columns will lower, releasing Iron Liches. When you step inside the column, the entrance to the room will close, sealing you inside. After picking up the Blue Key, you'll need to get to and step onto one of the lowered lava columns, which will unseal the room. There are items on the lowered columns, including a Map Scroll and two more sets of Wings of Wrath, for a total of four sets in this level (the most in any level in the game). Furthermore, there are Inferno Orbs and other items down on the lava.
Although flying to the columns is the obvious thing to do, it's possible, although hazardous, to do it without flying. You'll need to time it just right so you won't be trapped inside by the shield, or fall down to and be stuck in the lava pool. (The shield is the way out of the lava if you do, but it moves slowly and may take too long to lower. You can get to the Inferno Orbs this way too.) To get to the column, jump to the shield when it's below the level of the lowered column, ride it up to the column, and quickly run across the column and back onto the shield before it's too high to reach and traps you inside. To get off the column without flying, you'll need to ride the shield up just enough to do a running jump to the nearest ledge or walkway. If you used all of your Wings of Wrath before coming here, jump to a column with Wings first, and fly the rest of the way, unless you truly want the extra challenge.
Big watery room and side areas
Go back outside and enter the Blue Door. In here is a narrow meandering corridor in a loop. At the far end is a wooden door. You can go in there now, or save it for later. Look along the inside of the corridor for a section where the texture is different (the "rough" surface, not the tapestries); it was a bit to your right when you first came in here. Activate it to open a door, step up to the Phoenix Rod inside, and doors ahead and on either side will open. Watch out for a minor ambush, then hit the switch you find past the door ahead. Back in the corridor, two more doors have opened, leading to side rooms with lots of Disciples of D'Sparil, so have a weapon ready. In each room is a teleporter that leads back to one of the side rooms along the main corridor above the courtyard (specifically, about where the Wings of Wrath were), and a window looking into a large, tall, water-filled room with a set of big platforms at one end. That's the room through the wooden door in the corridor. If you went there first, the only enemies you would have found were a bunch of Gargoyles, but you also would have attracted the attention of some of the Disciples of D'Sparil through the windows. If you go to the side rooms first, you'll attract the Gargoyles and can fight them through the windows.
Go through the wooden door to the big water-filled room. When you hit the switch earlier, the wall at the back of the uppermost platform opposite the room opened, with the level exit inside.