Vulnerability procs have a chance (ranging from a small percentage chance to 100% chance) of being gained in battle.
Vulnerability procs are gained at the start of combat.
The amount of additional damage from a vulnerability proc varies depending on the vulnerability proc's level:
Level 1 +5% of final damage-type total Level 2 +10% of final damage-type total Level 3 +15% of final damage-type total Level 4 +20% of final damage-type total Level 5 +25% of final damage-type total
If you have more than one item in your setup with a particular vulnerability that procs, the amounts of each vulnerability are added together to determine your total vulnerability.
Vulnerability and dealing the same damage type
Particularly with coven bosses, you may fight an opponent that deals the same type of damage that they are vulnerable to.
This is a perfect example of why you should consider an opponent's entire range of procs and feats, as well as each proc's level, when selecting a weapon and set of vampiric powers to use against that opponent.
A damage-type vulnerability can be a useful starting point to defeat an opponent. But it may also be the wrong choice. Think before making an "easy" choice!
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