I think a interesting "weapon"(if it comes to a weapon) would be Measure from FFXII

Measures
Measures have low attack ratings, but ignore defense when used, damage being calculated based solely on the weapon's attack. Measures also cause beneficial status effects on hit, so they are to be used to strengthen the party without using MP and should generally be switched out for more conventional weapons after being used. Measures add 25 evasion, which, along with the ability to equip shields, makes a character equipped with a measure difficult to hit.

Measures are also effective when attacking characters to remove the confuse status since Measures do not deal heavy damage yet they can confer beneficial statuses. Unlike other melee weapons, measures have a chance of dealing critical hits. Targets cannot parry or block measure attacks, but the wielder can still miss due to bad accuracy. Measures cannot knockback enemies. Measures have the same speed as hammers and maces at 2.63s charge, and 1.2s action time.