The Void
The Void has 60 health.
It takes extra damage from spirit; it resists blunt, slash and pierce; poison does nothing to it at all.
Its only attack is ghost attack, 25 slash.
Of everything craftable, 
Lightning Strike, 
Frostfire Crossbow and 
Frostfire Sledge put the most damage through what it resists.
The Void is an Undead creature with 60 health that resists blunt, slash and pierce, is immune to poison, and is weak to spirit. It drops 1 to 2 
Ectoplasm on a 50 percent roll and carries no trophy, a thinner table than the 
Ghost it shares its stats with, which drops 1 to 5 every time. It walks at 5 meters per second but runs at only 4, so it is slower chasing than wandering.
Its attack is 25 slash, the weakest of any new creature, so the danger is nil and the resistances only mean it takes two swings instead of one. Drops 1 to 2 Ectoplasm half the time.
With devcommands enabled, this spawns The Void in front of you. The third number is the level: 3 spawns a 2-star.
Creature ID: Ghost_old · all console commands and IDs