Whenever the FF player wins a battle, the party members will strike a victory pose.
In the earlier games, these were generic and universal across all characters, but as the series progressed, the characters began to have unique victory poses, with some even changing as the story progresses.
Cloud pumps his fist twice, spins his sword in one hand, and then places it on his back. His signature has been carried into other games as well.
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Fun lil video !