Beacon Bow (5e Equipment)
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Weapon (any bow or crossbow), uncommon
You can activate the beacon effect by thought while firing a nonmagical arrow or bolt from this magical weapon. A nonmagical arrow or bolt emits a fizzing red glow when it hits a creature. While the creature is under the magical effect, it cannot have any benefits from being invisible, hidden, or by being behind half cover. Only one creature can be affected at a time. The creature can use its action to remove the arrow, or you may use a bonus action if you are within range. The existing effect also disappears when you activate the beacon effect again while firing.
When you attack a creature with the beacon bow and roll a 19 or 20 on the attack roll, further attacks against that creature are made with advantage until the start of your next turn.