Ghost has 60 health and spawns in Black Forest.
It takes extra damage from spirit; it resists blunt, slash and pierce; poison does nothing to it at all.
It has one attack, 25 slash.
Of everything craftable, 
Lightning Strike, 
Frostfire Crossbow and 
Frostfire Sledge put the most damage through what it resists.
It always drops 
Ectoplasm.
Ghost is an Undead creature found in Burial Chambers in the Black Forest and during the "You feel a chill down your spine" raid event. It has only 60 health but resists blunt, slash and pierce, so bronze-era weapons chip rather than cut; it is immune to poison and weak to spirit. It scratches for 25 slash every 2 seconds within 1.2 meters, a heavy hit for the tier it turns up in. Every kill drops 1 to 5 Ectoplasm and the 
Ghost Trophy at 10 percent.
They die to anything eventually, just slowly. Keep your shield up, trade patiently, and remember they never respawn: a cleared chamber stays cleared.
With devcommands enabled, this spawns Ghost in front of you. The third number is the level: 3 spawns a 2-star.
Creature ID: Ghost · all console commands and IDs