Ok, in the town of Silverglen I turned down Brandon's quest. I was roleplaying my Source Hunters as kind of honorable guys and he seemed shifty. I should note that I did not realize at this point that this was one of only two ways to learn the Tenebrium skill. Many many hours later I was wandering Sacred Stone and found the book "How to handle Tenebrium", simply assuming that it was a regular book I had Jahan read it as he was my scholar and also convinced that Tenebrium was somehow demonic (There is that nasty roleplaying thing again). I was surprised when he learned the Tenebrium skill, bemused I wondered when everyone else would learn it, not realizing I had now locked out both of the only ways for a character to learn the skill.
Cut to about 8-10 hours later where having fully explored the map I finally get to the entrance to the volcanic north west and ZixZax tells me I have to close the void and I will need a Tenebrium weapon to do so. Which brings us to the issue. There are no Tenebrium Staffs as far as I can see, at least I have never found any, there are none for sale and there seems to be no way to craft them. So yeah. Stuck. Noone to damage the Blood Stone, no way for anyone else to learn the skill. I can reload but its many hours (And a whole character level plus many cool weapon drops and a bunch of crafting) lost. About 10 hours play lost all up
Further details:
Jahan is a pure spell caster with all his skills in aero hydro and pyro. His Dex is 5 and his Str is 5. So this rules out melee weapons and bows. Even using the buff books from the secret seller at the homestead I cant get either stat high enough to be able to use a good weapon.
Even if there were Tenebrium Staves you need a weapon that does pure Tenebrium damage and all staves are elemental
I tried hiring a hireling but Im level 16, so the highest level one I can get is 12. He had no Tenebrium skill to begin with I buffed him with a book from the secret seller. But at level 12 he is just to fragile to survive. He might as well be made of glass and have a target painted on him.
I tried taking some Tenebrium ore to Brandon in the kind of vain hope that somehow shoving it in his face would make him teach me the skill. It didnt.
I thought maybe what taught the skill was an item on Brandon so I tried pickpocketing him. That just made the guards come. So I killed everyone in Silverglen. It didn't help but it was very cathartic. There was no magic "Get Mandrake out of the crap" item anywhere on Brandon's corpse.
Conclusion:
So there we have it. I've managed to royally shaft myself. I realize this is a rare circumstance but If I can do it others can. It is not a bug but it does seem poor design that through regular gameplay you can lock yourself out of the main quest. I now have no choice but to go back before I had Jahan read the book (Many hours ago)
Suggested fixes:
1) Don't lock off Brandon's quest.
2) Have a popup on the book that says "Are you sure you want this character to learn this skill"
Without some warning on this seemingly innocuous book someone else will just innocently break the main quest too,
