E2M8: The Portals of Chaos (Heretic)

E2M8: The Portals of Chaos is the eighth level in the Hell's Maw episode of Heretic.

Walkthrough and secrets
The level is structured so that there is a large path that goes in a circle on the outer bounds of the level, and an inner structure that is concealed by walls. The large path that is closer to the outside of the level contains the standard monsters and alcoves of pickups. The inner structure is where the maulotaur fight will take place. To reduce the chaos, clear out all of the monsters in the outer ring. Collect the items that are scattered around the map as they will be useful in the boss battle.

In the western section of the outer ring, there will be a mound of land that is occupied by nitrogolem ghosts, and contains an Ethereal Crossbow. Get to the top of the mound and a secret compartment will open behind a wall of stone at the edge of the map. In the compartment, there are some items including an Enchanted Shield.

At the southern end of the circle, there is a crevice with a Dragon Claw on a podium. Stepping on the podium will open a rock wall across from the stairs to the east. There is a crusher trap inside, and it can be artfully dodged in order to collect the pickups at the end. The area is the second one of the two official secrets in the level.

Across from here, you will see a staircase. When ready, go up the stairs and collect the Mystic Urn at the top. Down the other side of the staircase, there is the entrance to the inner structure. Depending which skill level you are on, you may have one (skill 1 and 2) two (skill 3) or three maulotaurs (skill 4 and 5) to fight.

When going down the staircase to the inner structure, make a beeline for the Ring of Invincibility. It will awake the maulotaurs. Circle around them in a way that will group them together. If you cannot group them together, then start by using the powered-up crossbow, and use the Ring of Invincibility to avoid damage from attacks on all sides. If you can group them together, use the powered-up Hellstaff, which will rain upon the group of maulotaurs.

Another strategy which may require more skill (but is unlikely to cause any trouble to experienced players) is to quickly run from the starting point to the staircase connecting the inner and outer parts of the level. The walls between them will then lower and allow for a gigantic monster infighting. Run in big circles across the level, attracting the monsters to the central part and picking up weapons and items. By doing so, you will have the maulotaurs being accidentally hit by other monsters and fighting them back, providing you with a possibility to conserve ammo. With the use of the strategy, the level can be easily completed even if you have started with only an Elven Wand, and if done perfectly, you will only have to fight maulotaurs in the end. It is not even necessary to visit the little ammo caches adjacent to the outer part of the level.

It is a bit tricky, yet possible, to lure the maulotaurs (one or more of them) under the crusher in a room at the edge of the map. Ring of Invincibility is necessary for it if you have already accessed the room and activated all the crushers. Use the ring to get the maulotaur(s) into the confined space in front of the crushers and then run under the latter. Wait on the other side in a room with a teleporter (the one behind the secret door) and use the teleporter after the maulotaurs have been crushed (it may take a while). Another option is to use the Chaos Device to return to the starting point.

When all of the maulotaurs are dead, the exit portals will lower and you can exit the episode.

Bugs
The player 1 start (Thing 0) has no flags set for any of the three difficulty classes, but because of special handling in the engine, it functions normally in the level.