Rider's Sword (5e Equipment)
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Weapon (any sword), rare, very rare, or legendary
Rider's Swords are magical swords with either a +1, +2, or +3 bonus to attack and damage rolls made using it. This bonus depends on the rarity of the sword: rare(+1), very rare(+2) or legendary(+3).
When attacking with a Rider's Sword, if the target's AC is magically increased (spell, magic item, etc.) or if they would take reduced damage through magical means (including if a spell or magic item grants resistance or immunity), you may ignore the AC bonus and/or damage reduction (Does not ignore spells that target you and reduce damage you do, only magical effects that reduce damage the target takes. Also does not ignore resistances and immunities not granted through magic).
If you are a Dragon Rider with a Dragon Rider level of 10 or greater, you may use the Rider's Sword as a 200gp, 400gp, or 1,200 gp gemstone.