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These moves require their user to sacrifice a portion of their maximum HP in order to use them. Depending on the move, it may fail without deducting HP or succeed but KO the user if they do not have enough HP remaining to use it. Moves in this category are similar to but should not be confused with moves that cause recoil damage, which deal damage to their user as a side-effect of their successful use (and thus can be used without recoil if the user has Magic Guard), or moves that cause the user to faint, which outright render their user unconscious in order to be used.
Pages in category "Moves that cost HP to use"
The following 4 pages are in this category, out of 4 total.