Retractable arm sword (s) (3.5e Equipment)
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This weapon is meant to be similar to the hidden blade from "Assassin's Creed" with a few major changes. First, the blade is now on the top part of the arm as opposed to under the arm. Second, the blade is longer, more closely treated as a longsword instead of a dagger.
As a Free Action the blade is sprung forward, and due to the quick action and concealed location the first attack made with the Arm Blade treats the foe as Flat-Footed. The blade must be retracted for at least three rounds to gain this bonus again. Treat as a Longsword with a Locking Gauntlet. While hidden, an opponent can spot the Arm Blade by succeeding at a Spot check verses the player's Slight of Hand check, which has a +10 Bonus.