Volatile (3.5e Equipment)
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Volatile: A Volatile weapon deals no physical damage, unlike most weapons. Instead, it deals 5 points of damage on the first hit against a creature and reduces the target's AC by 2. On every hit after, this damage increases. Two hits in a row deals 5 acid damage and reduces the target's DR and AC by 3, and stuns the target until the beginning of your next turn (Fortitude DC 18 negates). The third hit deals 8 acid damage and reduces the target's AC by another 3. Four hits deals 10 acid damage and slows the target for 2 rounds. The fifth hit hits deals 15 acid damage and reduces the target's AC by 7, to a total of -15 AC. On the fifth hit, the acid spreads out and deals 5 extra acid damage every round for 5 rounds. After five subsequent hits, you deal 10 points of acid damage plus one per hit you have made in a row (The sixth hit would deal 16 damage, ect). If you miss, you restart at the first hit. You cannot reduce a single target's AC by more than 15. If you reduce a creature's AC by fifteen, reduce DR and SR by 1 point per hit. None of these scores can be negative.
Creatures immune to acid are entitled to a save (Reflex DC 15 + effective enhancement bonus) to avoid the damage and a DC 20 + enhancement bonus reflex save to avoid the side effects. Resistance to acid only allows the save against the damage.
Moderate Abjuration;CL 14; Craft Magic Arms and Armor, Melf's Acid Arrow; Market Price: +4 bonus