Although he couldn't see the effects now, Aiwass had long memorized the effects of these two rare skill effects.
Helping friends grind through advancement dungeons, he could recite the random skill effects that popped up...
Good deeds bring good karma.
"Tainted Light" is a high-tier skill effect that, in theory, can be fully activated three times.
Its effect is such that when a spell that exclusively uses Light Attribute Mana deals damage, it adds an additional third of that damage as poison damage. Upon activating this skill effect a second time, another third as cold damage is granted. When activated for a third time, it adds yet another third as shadow damage.
If one were to fully activate this skill effect all three times, they would end up with a straightforward 100% bonus damage. Additionally, because the bonus damage is composed of three different damage types, it's not easily negated by attribute resistances.