Level 1
Slipgate Complex

Level 2
Castle of the Damned

Level 3
The Necropolis

Level 4
The Grisly Grotto

Level 5
Gloom Keep

Level 6
The Door to Chthon

Level 7
The House of Chthon

Secret Level
Ziggurat Vertigo

You've successfully passed through the Door of Chthon, and you've now arrived at its House. Who - or what - is Chthon? To find out, grab the silver rune at the entrance.

If you don't want to spoil the ending of this episode, stop reading now!

Defeating Chthon - Emptying your weapons into Chthon is futile. Even with the sole power-up found in this level (a 100 health bonus), you can take only a couple of hits before you are fried to a crisp. Put your gun away. Brute force doesn't count here. To beat Chthon, you're going to have to use your head.

Your final Quake conflict...at least until the episode	Step on a switch...
...to lower an electrode	Throw the central switch trigger to fire the electricity

After Chthon dies, a platform appears over the lava pit. Walk to its center, jump into the marked shaft, and step through the teleporter. And what of the other 20 enemies that are supposedly in this level? Watch the level's ending to see their fate.

Instead of grabbing the rune at the beginning, it's a good idea to explore the level and get some practice tripping the switches.

There are no secrets in this level. Nor are there additional weapons to be found.

It's not necessary to run (the Shift key) as you move along the upper deck. A brisk walk will suffice. Unless you actually stop, Chthon isn't likely to hit you.