REKT (Rapidly Escalating Kill Tactic) Weapon (5e Equipment)
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Weapon (any), legendary (requires attunement)
This enchantment shouldn't exist. But thanks to the ruthlessness of a long dead mage and the apathy of the fates it does.
That Escalated Quickly. When a creature is first hit, after damage is resolved, it must make a DC 13 Constitution saving throw. On failure, the creature becomes affected by an increasing set of effects until the end of your next turn. If you continue to hit the creature on subsequent turns, the effect continues to extend until the next turn, and increases/the next affect applies in the following order:
The effect progression continues unless you miss, do not attack, attack it by different means or attack another creature, at which point all effects (but not the damage) are immediately removed. If you attack them again, they make another saving throw, potentially resisting the effect. A creature that succeeds on the saving throw cannot be affected again until you have killed another creature or 24 hours have passed.
No Mercy. If you roll a natural 1 when attacking with this weapon, you immediately take the full value of what the attack would've dealt as a critical (including vulnerability, if applicable) plus an extra d6 for every effect level you had active on the creature you were attacking. This damage is psychic and cannot be resisted or reduced in any way. If you are reduced to 0 hitpoints as a result of this damage, you die instantly.
Unnatural Enhancements. If you kill a target with a critical strike, you can enhance the enchantment of this weapon in the following ways:
Enhancing the weapon requires re-attuning to it during a short rest, after the criteria is met. All enhancements reset if you unattune the weapon, drop to 0 hitpoints, or die.