Ghosts are mobs that are encountered in the Twisted Dimension.
Ghosts have very high health, at 40 hearts, but deal the lowest possible damage at only one half-heart. They ignore most other mobs, but are hostile to the player if looked at, similar to Endermen. Unlike Endermen, they cannot be sated by wearing a pumpkin.
The ghost has a translucent white appearance and lacks any discernible facial features, but is humanoid in shape. It floats above the ground slightly, but can still fit through 2 block tall passageways. The ghost can float down from great heights similar to the way chickens glide, and is immune to fall damage as a result.
Though the damage they deal is low, ghosts are persistent due to their high health, and can knock the player into the void. To kill ghosts, it is recommended to use the Smite enchantment. As they are undead, they can also be damaged by hitting them with potions of healing, but potions of harming will restore some of their health.