Rebellion (5e Equipment)
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Weapon (longsword), legendary (Requires attunement by any chaotic alignment.)
Rebellion is a massive claymore with a heavy double-edged blade, notched on both sides near the tip. The guard is skeletal, with a skull-design on each side leading to the rib cage from which the blade emerges; on one side of the blade, the skull is that of a human, while the other uses a horned demon's skull. Rebellion is a sword of an ancient dead demon called Sparda, whoever touches it will feel an evil and chaotic energy flowing in it. Only chaotic peoples will want to use it.
The Rebellion is a remarkably powerful magical sword. It is sharp enough to cut the skin of a god, and has a +3 bonus to attacks and damage rolls, besides being unbreakable.
If attuned, you can spend an action to command it to fly up to 30 feet and attack a target of your choice.
(Alternatively you can periodically make the user past in a wisdom saving throw DC10 or will transform into a chaotic demon controlled by the master for 1d4 minutes or till be knocked unconscious.)