The Void is somewhere you don't want to be, at least for long. In the list of planes, it's the rightmost one (the totally black sphere), but there's only one comprehendible province in the Void anyway. Void exposure is typically self-inflicted.

The one comprehendible province in the Void is Nexus, an odd place with the eponymous Grey Tower. It is always 5 here, which is neat for research but terrible for long-term stays. It also provides 5 per month, and a 20% discount for all Alteration rituals. An order of Grey Knights with magic swords and a limited tether to reality runs the tower, which is also staffed by Shadow Seers.

Nexus is accessed through forging a Nexus Gate, a Level 9 Thaumaturgy which requres 53 and 40. This forms an eternal connection between the province you cast it in and Nexus itself. If you cast Nexus Gate in Nexus, nothing happens. Note that anyone else who casts Nexus Gate will also end up making a connection to Nexus, and that rituals can trace through Nexus if they have a range to them.

To end up outside the Nexus but still in the Void, you normally have to screw up:

• 7% of people who use Returning or Vortex of Returning will end up in the Void instead of back at home.
• Messing up with the Void Gate that middle and late R'lyeh have might get you stuck inside… or is it "outside"?
• Being hit by the Dimensional Rod teleports you to the Void, though that's an artifact.

Outside of Nexus, the odds of being attacked by something are far higher than the natural rate of chaos from high-Magic Horror Mark buildup. Every turn, there's a 15% chance of an attack. The foes that hunt you won't be Horrors, since they aren't looking for random fellas floating around, but they will be serious.

Not having a floor to stand on, or any real need for food or water, is very taxing on the mind. It causes a drn (one exploding six-sided die) of Insanity each turn, divided by your Void Sanity. The Mindless cannot go insane, of course.

There's about a 5% chance each turn that you fall out of this empty space, and into some random province. This has a 30% chance to "enlighten" you, giving you +1 and 2d50 Insanity (also exploding) if you're not already 4 or higher. There's a 10% chance that you "direct" your fall back to one of your nation's provinces, plus 20% for each of your Astral levels; otherwise, the location is completely random. No one knows if you're more likely to fall into Nexus than any other province.

Void Combat sucks. If your Void Sanity isn't any higher than 1, your Attack Skill, Defence Skill, Precision and Magic Resistance are all halved by Dimensional Overload. For reference, those without Void Sanity on their character sheet are considered to have Void Sanity 1.