Ghosts are an undead unit associated with Shipwrecks, serving as a fourth tier unit in the video game Heroes of Might and Magic: A Strategic Quest. They cannot be recruited in any manner, and can only be found in Shipwreck creature banks. Although certainly not the strongest creature in the game, they are by far the most potentially dangerous, far exceeding even Dragons under the right (or wrong) conditions.
The difficulty in fighting ghosts lies in their creature ability, which causes them to convert any creature they kill into another Ghost for their stack. Because of this, a hero must never use low-tier creatures when fighting Ghosts, and especially not Peasants, which will simply be converted and used against you while being far more powerful as Ghosts.
Ghosts can be found inside of Shipwrecks found along coastlines. In Heroes I, the hero fights ghosts (usually around 200) and will be rewarded with gold.