Teräs Käsi was a form of hand-to-hand combat that was created to fight Force-sensitives, particularly members of the Jedi Order. Melee weapons could also be used in the combat form. Its practitioners were ranked into novices, adepts, or masters according to their skills level, and wore distinctive outfits.
Former Sith Lord Maul, the head of Crimson Dawn, was a practitioner of Teräs Käsi, and he taught it to Dryden Vos, who, in turn, trained his lieutenant, Qi'ra. During the raid on Kessel, Qi'ra utilized the form to take down Quay Tolsite of the Pyke Syndicate. Very few people alive during the Imperial Era even knew that Teräs Käsi existed, with even less actually knowing how to fight with it, making her unique.
The Emperor's Royal Guards of the Galactic Empire were trained in the form. The Elite Praetorian Guards of the First Order were also trained in Teräs Käsi, along with other martial arts.
In the current Star Wars canon, Teräs Käsi was first mentioned in the 2015 mobile game Star Wars: Uprising. Teräs Käsi originated in the 1996 Star Wars Legends novel Shadows of the Empire, before being showcased in the 1997 fighting game Star Wars: Masters of Teräs Käsi. It was created by Steve Perry, who is a practitioner of, and was inspired by a real-life fighting style called pencak silat.
According to writer Gary Whitta, cut content from the 2016 Star Wars Anthology film Rogue One: A Star Wars Story would have established that Saw Gerrera taught Teräs Käsi to Jyn Erso.
"Teräs Käsi" is Finnish and translates directly as "Steel Hand," although normally in Finnish it would be written as a compound, ie. "Teräskäsi." The name is also an allusion to the video game series Tekken by Namco (which translates to "iron fist" in Japanese), which was a direct source of inspiration for the Star Wars Legends video game Star Wars: Masters of Teräs Käsi.
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