Valen Dreth 1 versus Valen Dreth 2! (Spoilers?!)
Did you know that there are two Valen Dreths?! Did you know that the sewer gate you exit from doesn't lock and get a message posted on it, unless you join the "Dark Brotherhood"?
Playing on an "X-Box" or something like it, I guess it'd be more apparent as to why. Because on such systems, you have no choice but to re-enter a place more than once, if you want to empty the place of all loot, no matter how worthless it may seem at the time. At least, that was how I had to do it when playing the game on my brother's game system. Which I didn't do until after I'd been playing on mine for awhile.
I play using the PC version. I learned about the game from watching my best friend playing on his PC. I remarked that it was too bad that they didn't have a "Bag of Holding". However he had the topless unlocker mod. When he explained to me what a "mod" was I realised that someone out there would have made a "Bag of Holding". So when I eventually got my own copy of the game and a PC good enough to play it on, I began hunting for mods.
So for the most part, I've only played with mods installed. So I didn't have to make several trips to loot just one place. I could do it in only one trip! Hence the delay in noticing that there's something about Valen Dreth, as opposed to Mary.
Some players can't wait to kill him off in that DB quest, because of the taunts at the beginning. However, I'm here to inform those of you that don't already know it, that the one you kill off in the DB quest, is not the same one that taunts you in the beginning! Heck, you aren't even in the same cell!
That's why you can't backtrack the exact same path to get to him, that you used to get away from him! The detour takes you to an alternate cell area with who I like to refer to as, "Valen Dreth II"!
So now I've taken to rescuing "Valen Dreth I", along with the non-hostile "Sewer Rat" whom I rename, "Splinter the Magical Sewer Rat", before I leave the area for good, before the "Langoliers" get them!
Each Valen Dreth has his own number to allow him to be set essential. So you can have two of them in your army if you want. (Yes, kill 2 off first to do the needed quest stage advance. But then simply resurrect him afterwards, one way viai spell, or another via Console Window command.)
Ta-dah!