Dateiliste

That's the level with the Humonculous at the end. You need 2 icons to gain access to a third one, which finally lets you in to fight the Humonculous.

A complete walkthrough for this level is at Moon's Descendarium - Retribution level 6 (Martian Nomad Caverns) (spoiler), as usual.

The level is good for co-operative, anarchy, and robo-anarchy. For robo-anarchy it is most likely best to play it at least in hotshot or even insane, because the level doesn't contain any particularly difficult robots. The level cannot be played in any of the other game types like CTF etc.

The level has several glitches, but their encounter is very rare if your Descent 3 version is at least 1.4 (and this should actually be the version you should be using). (See below.)

Spoiler: It is easier to kill the Humonculous with heavy Vauss fire. Secondary weapons seem not to hurt him very much, no matter how strong they usually are. Don't waste your valuable missiles in single-player on him.

Spoiler and glitch: To get into the mine you need to destroy the two blocks with red lights next to the elevator platform's gear rods. Unfortunately, while outside you may encounter a couple of flying saucer robots that fire concussion missiles (I don't mean the flying vessels with the little monks inside). If one of those concussion missile bots destroys one or both of the blocks with the red lights, you can't get inside the mine anymore. The elevator is only triggered if the player destroys both gear rod blocks. If a bot has blown one of them up, you need to restart from a saved game (in single-player) or restart the level (in co-op).

Here's the video walkthrough from NUMBERZero for Descent 3: Retribution level 6 (Martian Nomad Caverns):