E1M5: The Citadel (Heretic)

E1M5: The Citadel is the fifth level in the City of the Damned episode of Heretic.

Walkthrough
You begin the level by a river between four buildings. Head west and go up the stairs outside the northwestern building. At the top, dash across the gap to the upper level of the southwestern building and locate the Gauntlets of the Necromancer, a Silver Shield, and the yellow key. Use the yellow key to enter the northeastern building. Pull the switch to raise the stairs outside, then head to the top floor of this building to collect the Ethereal Crossbow. Now enter the southeast building and go upstairs to find the green key on the balcony. Head to the south of the area and go up either set of stairs to find a green door. Pass through and pull the switch to lower the red barrier. Head down the passage that is revealed and go through the second door to the side. A barrier lowers to reveal another outdoor area with a large building. Find the blue key in the water to the south of this area and take it to the blue door at the north end of the area. Pass through, turn left, and go behind the stairs to find a switch. Pull it to open the exit door. Now climb the stairs and head to the exit.

Secrets

 * 1) Inside the top floor of the northwestern building in the first area, press the wall to the right of the door to open a secret chamber with ammo.
 * 2) Go to the northeastern tower in the second area and walk on top of the wall bordering the stairs. You will see a building with Timebombs of the Ancients. Dash across the platform and onto this building to collect them as well as a Ring of Invincibility.
 * 3) There is a niche at ground level in the west side of the building in the second area. Inside you will find a switch. Pull it and head outside to the north to find a lowered platform. As the platform begins to rise, dash into the niche that contains a Morph Ovum to earn a secret. If you ride the aforementioned platform to the top of the building, you will find a non-secret area containing a Dragon Claw.
 * 4) Inside the eastern half of the building in the second area, you will find stairs to the basement. Go through the teleport that you find here to reach a secret area. From here, take either teleport to collect the Wings of Wrath and a lot of ammo.

The following places do not give credit as a secret areas:


 * 1) After collecting the green key, dash off the balcony and into the well to get a Tome of Power.
 * 2) From the northwestern tower in the second area, dash across to another Tome of Power. Pull the switch to lower a barrier between this platform and the rest of the building's upper level.
 * 3) After passing through the blue door, go up the stairs and drop into the well to collect the Wings of Wrath. Use them to reach the items in the windows. Alternatively, you can use straferunning "jumps" to reach most of the valuable items.

Bugs

 * Outside the door of the chamber that holds a Shadowsphere, sidedef 759 is missing its lower texture. The error causes the wooden floor flat of the door threshold to leak over its bottom wall. However, since the threshold is only eight map units high and the adjacent walls happen to have a board pattern that matches the height and the color of it, the anomaly is well masked and can only be spotted with a closer examination.
 * Behind a corner, west of the blue door, sidedef 1,822 is missing its upper texture. As the top wall lies considerably high from the floor of the sector and can only be viewed from a diagonal, restricted angle, the leak glitch caused by the lower ceiling is also difficult to see. Nevertheless, if the blue door is watched from the southern end of the little pool that lies in front of it, the bug can be noticed well as the wall's symmetrical counterpart on the other side has its upper texture, CSTLROCK, set correctly.

Trivia
Interestingly, two golems have been flagged to appear on the multiplayer mode. As they lie at the opposite ends of the map, one being in the western tunnel and the other in the eastern, it is not clear whether this was intentional or caused by an editing oversight.