Lunge Mine (5e Equipment)
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Simple Melee Weapons
In 1945, the Imperial Japanese Army officially adopted arguably one of the most ill-conceived weapons of all time, the Shitotsubakurai (literally translated as lunge mine). Consisting of a wooden pole with a powerful explosive in place of a spear tip, soldiers were expected to pull the security pin situated at its head before charging head-first at an enemy tank. At the very least, a soldier wielding such a weapon could be assured a painless death relatively confidently.
Primed. If this weapon is not primed as a bonus action, attacks made with it act identically to those of a quarterstaff. After priming, they benefit from all features of this weapon. After making one attack with a primed lunge mine, it is destroyed.
Explosive. Attacks made with a lunge mine can be made at either a creature or object or a point within range. A creature whose AC is hit by a shell attack cannot attempt a saving throw to reduce the damage taken. Each creature within 10 feet of an exploding lunge mine must make a DC 15 Dexterity saving throw, taking the listed damage on a failed save, or half as much damage on a successful one.