Hi guys, with the help of the developer console I've been testing this interesting skill extensively... Basically, if you didn't know, this skill allows luck affect damage spells by Warlocks.
1. The big BUG that I've found (and mentioned elsewhere too but unconfirmed until now) is that the skill NEVER APPLIES TO EMPOWERED SPELLS... This is such a waste, since we all know that if you're going for Dungeon spellcasting, the backbone of your spells is that special ability... I hope Ubi fixes this in the future...
Other things of interest:
2. The Warlocks luck skill works for area-effect spells like Stone Spikes as well (again, non-Empowered only).
3. The Warlocks luck skill, when using area-effect spells, you DO NOT need to have a creature center-targeted for the luck to be attempted.
So, this interesting and unique ability is pretty cool right now, except for the bug with not working with empowered versions of spells... Can someone please try to contact Nival/Ubisoft about this? It seems like this will be an easy bug to fix....