Blade of Fortune's Bane (5e Equipment)
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Weapon (any sword), legendary (requires attunement)
This magical blade is ornate and seemingly impossibly made. That impossibility stems from being apparently completely made out of a single refined diamond.
Stored Critical. This sword has a +3 bonus to its attack and damage rolls. When you get a critical hit with the sword, you can choose to make it a normal hit instead. If you do so, fate bends and contorts around the momentary skill and luck, storing that potential in the blade. While the sword has this potential stored in it, it produces a dim light out to a radius of 5 feet. At any time while this sword has that potential stored in it, you can choose to turn any normal hit into a critical hit, or any miss into a hit. Once you do so once, you must store another critical hit in the blade to use this feature again. If you get a critical hit while you have that potential stored within the blade you automatically miss instead, and the stored potential is released without use.
Particular Worth. You can only use this sword as a material component for a spell that requires a diamond if you are attuned to it. Doing so destroys the sword, even if the spell otherwise wouldn't consume the component. This sword is otherwise unbreakable.