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A Grand Ghost is a large, humanoid creature with white skin clad in a faded red coat with black cuffs. It seems to wear an ascot under the coat. It wears white gloves with yellow fingertips on its large, long-fingered hands, which are not directly connected to the Heartless's body and can be "thrown" at enemies. A few holes in this coat expose the creature's ribcage. Its Heartless emblem is printed on the front of its coat. The Grand Ghost's spherical head sports a jagged mouth and two yellow eyes with black spirals in them. Its eyes appear more stable than its relatives', as neither eye is hanging from its socket. It can generate spotlights from its eyes, suggesting that they may be mechanical. The Grand Ghost's lower body is plain white with a ghostly tail. Both the Grand Ghost's tail and the undersides of its hands are tinted green, giving the appearance that a green light is shining on it from below. This is due to the fact that it only appears in Monstro's stomach, which is filled with green acid, and so it was intentionally designed with its location in mind.
The Grand Ghost's name may refer to its Victorian-style clothing, only worn by the sophisticated and "grand". It could also be considered "grand" as it is larger and more powerful than the original Search Ghost.
The Grand Ghost moves similarly to the Search Ghost. However, it cannot be confronted normally, as it is immune to physical and magic attacks and will retaliate if attacked in such a manner. Rather, for its HP to be depleted and for it to drop items, Sora will have to use healing items on it.
Therefore, use items such as Potions, Mega-Potions, and Elixirs to do damage to this Heartless. The probability of the Grand Ghost dropping Frost Stones depends on which items are used on it. For example: if an Elixir and two Hi-Potions are used, there is a chance of getting two Frost Stones.