Vollomyr Niltheor-Dun

Vollomyr Niltheor-Dun, the mage House Emberheart showed the door

Ask Khardum what a mage is allowed to look for. You will be told: whatever the stone is willing to hold, and nothing past it. Vollomyr had the talent to go far inside that limit, he preferred to know what lay behind it, and he wanted to see what a rune becomes when nothing holds it anymore. House Emberheart never gave him back his keys. He still sends them his work every season, and he has never once had an answer.

Describe him

He starts talking before you have finished introducing yourselves. His voice is warm, a little too high, and it does not stop at commas. He smells of ink, dust, and cold stone. His hands go into his bag while he talks and come back out with a book nobody needs. He always looks at you three seconds after he has answered you. And when he falls silent, he is not done. He is elsewhere.

Play him

Let him talk. Then let him talk some more. Give him a simple question and let him list the reasons to agree, then the reasons to disagree, then both at once. Have him mutter into his beard through the solemn moments. When someone cuts him off or shakes him, he comes back without taking offense and readily grants that he was elsewhere. And when the moment comes, let him pull from that bag the one book that names the thing the party is facing, open at the useful page, because he thought about it for the whole road where he seemed to be thinking about nothing.
Keep, underneath, a dwarf who is right about one precise thing and has nobody left to prove it to.

What he says (often)

"A rune holds power. Fine. What if we asked it for something else?"
"I can argue your side better than you can. Shall I try?"
(muttering, as the door gives way) "... or it is the exact opposite, obviously."