Martial Law (page 19-20)
Martial Arts Combat Styles
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Wrestling – This is an unarmed combat form with some similarity to Martial Arts Sweeps. It enables the character to engage an opponent in close grapples & locks with results resolved on the Grappling Critical Table. No skill ranks in Martial Arts Sweeps are needed.
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It's under the Martial Arts Combat Styles, but works like an independent skill.