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A Ghost Vase.
Ghost Vases are floating vases found in New Super Mario Bros. Wii. When the player gets close to a Ghost Vase, it will turn pink and fly into the air, rotating. However, it will eventually stop and rotate faster. After this, it will fly toward the player. The player can avoid the Ghost Vase simply by jumping over it or running away from it. If the Ghost Vase misses its target, it will continue to fly until it hits a platform or a wall, where it will break and release a Coin. In the World 7-, near the last Star Coin, the player can come across 4 ? Blocks that act similarly to the Ghost Vases.
Ghost Vases are mainly found in the World 3- and the World 4-.
A similar enemy called a Ghost Block appears in New Super Mario Bros. Wii and New Super Mario Bros. U.