Getting There
After you have killed Morgoth (in other words won the game), talk to Galadriel at Lothlorien and accept the quest she offers. A purple stairway called a jumpgate to the Void will appear a few paces away. This stairway will lead you to the Void.
Features
The Void is mostly empty, airless space dotted by nether mist squares and monsters. It is even more arena-like than most arena levels. The only walls are those of vaults and occasional areas of destruction on "destroyed" levels, if you have the applicable option turned on. The void tiles are the same black as unseen tiles and do not become visible even when lighted. However, they can be lighted permanently, even if the effect is non-obvious. As in the Maze, you instantly forget the dungeon layout when it stops being in your direct sight.
Monsters
The monsters consist of various non-living monsters, demons and dragons, all leveled up like in Angband. Various Spirits are special inhabitants of the Void and are seen nowhere else in the game. Every spirit is called simply a "Spirit", but looking at their colors and descriptions makes it possible to differentiate between them and anticipate their attacks. Look out for the spirit that is represented by a black G!
Guardian
The Void is guarded by Melkor, Lord of Darkness. He has an astonishing amount of hitpoints and he is dangerous beyond any single monster you have seen. You need to kill him to fulfill your quest.
However, to gain access to the bottom level you need to make a side trip to the Nether Realm, get the Flame Imperishable, and use it on a suitable object, thus turning it into an "ultimate" artifact, and then wear that artifact when you descend the final stairs.
Notes
Things you will pretty much need in the Void
- Magic breath (such as from a cloak of air)
- Ability to cause big damage
- Speed
- Resistances, immunities, reflection, everything you can get
- Hitpoints
- Healing and restoring of all important sorts, including sanity
- Detection
Things you will find highly useful
- Saving throw
- Stealth
- Some way of wall creation
- Targetted teleporting, void jump gates, and such
- Genocide
Magic breath, or the ability to breathe without air, is almost completely obligatory. If you don't have it, you need a source of unlimited big healing, and even if you have that, your fighting ability will be impaired by having to spend extra turns healing yourself.
You cannot recall from the Void or get out before you have killed Melkor. However there is a bug involving the Nether Realm that sometimes transports the player into Lothlorien.
Dungeon level 148 has a branch to the Nether Realm. This makes it highly dangerous since a bug causes the player to be deposited on a square that may not contain a staircase and so has to teleport away instead of ducking bad if there is something very bad like a demon pit nearby. You will need to solve this level at a minimum of two times.
Also, when you start your descent on the top of the Void you are deposited on a staircase but you can't go back through it, making it essentially like there was no staircase.
It might not look like it, but enlightenment is very useful in the Void. It makes various vortices, which are not detectable via telepathy, visible when they might otherwise breathe at you from beyond your light radius and you can also see right away when a stairway appears in your line of sight.
Detecting monsters is the only form of detection that works normally. Detecting doors and stairs is limited into the features blinking on the current screen and blinking out when the action is finished, making it impossible to detect farther from the player. In some cases involving destroyed levels a stair isn't detected in the midst of a destroyed area, but this is not always the case.
Be aware of the current targetting bug. It becomes noticeable especially when you are trying to hit something at the edge of your range. You may target something only to notice you couldn't hit it after all and waste mana/ammo.
LordEstraven: Monsters in the Void are supposed to be only demons, dragons, undead, and unliving, but they aren't. Icky things, molds, jellies, and other (living) low-level monsters were very common last I checked.
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