Sulla may have been part of the Imperial Legion, but possibly deserted to explore Alftand. Before going to the ruins, he gathered a crew to navigate the ruins: Umana, J'darr, J'zhar, Endrast, Yag gra-Gortwog and Valie. He left the expedition's manifest at the entrance of the ruins describing the members of the crew and the roles each one fulfilled for the expedition. His journal describes his ill-fated attempt at excavating the ruins, though he himself was undaunted by the tragedies. Inside, they found some Dwarven spiders that were disposed of easily, where afterwards he began taking them apart to research them.
When Sulla is first encountered, he is in a discussion with Umana. After a short conversation, they begin to fight until one of them kills the other or until the Dragonborn intervenes.
His fighting tactics are simple. He uses destruction magic as his primary attack and will use his Lesser Ward to block hostile spells should they be employed against him. When he runs out of magicka, he engages in melee combat. If his health goes very low, he flees from combat and uses Fast Healing. When his health has recovered enough, he continues to fight.
Umana "Sulla, let's just get out of here. Hasn't there been enough death?"
Sulla "Oh, of course. You're just waiting for me to turn my back so you can have all the glory for yourself!"
- After Sulla Trebatius is defeated, his body can be searched for an enchanted Imperial sword. Its enchantment type is random, but the strength of the enchantment is always the same (equivalent to 10 points of damage).
- It is possible that he may be a descendant of Vandorallen Trebatius from Oblivion.
- He makes a good dead thrall because his body is permanent, meaning he can be used multiple times if his location is known. His armor can be enchanted to make him stronger and he still heals himself during combat.
- As mentioned in his journal, he harbors a strong dislike of the College of Winterhold. He also appears to resent the Legion, as he states in his journal that he is "tired of all the credit going to the Legion" for whatever he had done in the past.
- He does not seem to be concerned that his foolish and ultimately failed expedition resulted in the deaths of his entire team, save himself and Umana, only worrying about who is going to get the "glory" of the discovery.
- His knapsack is in the torture room where Valie is found. Among its contents is an Imperial officer's helmet, along with a few common items.