Knavish Mercenary

supposedly the damage are dealt with the one you take so the less damage you take the less you do, or because it's a hp absorb the effect is weak

It pretty weak at the start but it is starting to useful lvl 10 and up.

Actually its not so weak. As mentioned earlier, you steal more depends on the amount of damage that you took in a single hit and its usually ore effective at higher levels. I just noticed it that a mage standing within melee range and casting a -aga spell on me and i survived, then it proc and i got tons of hp back.

it seems weak probably because the attack that proc it didn't do alot. If an attack hits you for 80% of your health and you survived while this procs, then you are healed alot. However, if you are hit several times before and then the next attack was like a melee attack that hits for 30 damage, then it will be a little amount.