Courage-Seeker (5e Equipment)
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Weapon (longsword), legendary (requires attunement by a creature of good alignment)
Courage-Seeker is a blade made by the most renowned adventurers of the ancient world. The weapon is eager to pick a fight, and go on an adventure. With this weapon, you gain a +2 bonus to all attack and damage rolls.
Thirst for Adventure: If you do not perform an Attack with this weapon against a non-Good or otherwise obviously hostile target, or enter an obviously hazardous or hostile environment (such as a dungeon), for 24 consecutive hours, it will begin to telepathically complain. It will also begin to complain if used to make an Attack against a Good-aligned, or obviously allied/friendly, target. While it is complaining, you have Disadvantage on all Intelligence, Wisdom, and Charisma-based Ability Checks. It immediately ceases to complain if it is used to make an attack against a non-Good target or enters an obviously dangerous area in the former instance, but in the latter instance only unattuning and reattuning the weapon, or waiting 1 week since the last time an Attack was made against a Good-aligned or obviously friendly target, will cause the complaining to stop.
Bravery: As long as you are wielding this weapon, you are immune to being frightened.
Supernatural Awareness: The sword innately senses hostile intent. Whenever a creature is within 30 feet of you and actively seeks to cause you harm, Courage-Seeker will alert you of its presence (though, not its distance or the direction in which it is located.)
Teamwork Mindset: Whenever an ally within 30 feet of you is attacking, you may use your Reaction to grant them Advantage to their next Attack check.
Curse - Kill Raiser: Each time you reduce a creature to 0 Hit Points via an Attack made with this weapon, it harvests and absorbs a fragment of their essence, gaining a number of Essence points equal to their Challenge (rounded up to the nearest whole number.) While Courage-Seeker is at 10 or more Essence, its Curse fully activates, and it gains a primal thirst for blood; its blade, too, flushes completely black, with nothing reflecting off of its surface. This results in the following:
While at 50 or more Essence, Courage-Seeker's necrotic damage increases to 2d6. While at 250 or more Essence, it increases to 3d6. Finally, while at 1000 or more Essence, it increases to 4d6.
Courage-Seeker loses half of its current Essence points every time its bearer completes a Long Rest after having not used it to make any attacks for 24 or more consecutive hours. Alternatively, becoming unattuned with Courage-Seeker will cause its Essence to reset to 0 after 24 hours.