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The Thunder Knuckle (サンダーナックル, Sandaa Nakkuru) is one of C. Viper's special attacks.
Description
Executed by performing a quarter-circle motion backwards and pressing punch, Viper suddenly moves forward, leading with her fist which is electrified by her glove. The direction in which she moves is determined by the strength of the punch button used: a medium punch sends her dashing straight forward while a light punch causes her to dash while crouching for a low attack, and a heavy punch sends her leaping diagonally forward, turning the move into an uppercut. This makes the attack capable of controlling horizontal space as well as vertical space.
The EX Special version of the attack is like the medium punch version, except that it covers the entire length of the screen and Viper does not stop at her opponent, even when blocked; she will continue on past her opponent, making the move useful for escaping a cornered position.