Just a note. There are some enemies that have more than 100% resistance to tenebrium damage (especially closer to the end of the game). If all your weapons are boosted with tenebrium you will have a hard time defeating those enemies. I normally have one of my heroes specialized in a specific weapon type and boost his/her weapon with elemental damage. Tip: Boost it with tenebrium damage first and then elemental damage to get the maximum possible damage. I have found that a mix of tenebrium and elemental damage boost makes me more flexible no matter what kind of enemies I face.