Vibro weapons

are a class of weapons with special adaptive penetration (PV) mechanics.

While most weapons have a specific penetration value that does not change, such as 6, vibro weapons adapt to the armor of the enemy, and a vibro weapon's penetration value is always equal to the opponent's armor value (AV). For example, if you attack a with AV 1, the vibro weapon's effective PV is 1. On the other hand, if you attack a with AV 25 with the same weapon, the weapon's effective PV is 25. As a result, vibro weapons can be extremely effective against powerful late-game enemies, especially for characters who have low strength.

A vibro weapon's adaptive PV is represented with a wavy equals sign in game: ( ≈ )

Penetration Chances
The following table indicates the chances of penetrating one or more times with a vibro weapon when a target is hit (for more about hit chances, refer to the Hit Roll topic).

The +1, +2, and +3 columns indicate the chances when a PV bonus is in effect, such as when you mod the vibro weapon with Sharp or if you're using Long Sword aggressive stance. For example, you can obtain a +3 PV bonus by combining a Sharp-modded vibro weapon with Improved Aggressive Stance.