100% not Uldren. Yeah, I know about the hunters dare and all, but I think we are forgetting something really important. Uldren has no F'ing experience as a guardian. How can he be a mentor, when he's only been alive (again) for such a short period of time. He's level 1, 10 light and hasn't even unlocked a full sub-call tree. In order to be a mentor you have to have experience as a guardian. So, no he won't be it. Besides, it would limit what they could do with him. He'd be stuck in the tower. Now, what if say every few weeks we see hints of him in the Queen's court. Similar to what we just saw. It would be a great quest for Penumbra where we have to track his @$$ down and bring him to the tower.