Hello! My character is around level 30 and has barely touched the main plot (I haven't gotten the horn of whatshisface yet. It has sat on my quest log for months.) I went a-wandering far to north, one day (like you do) and I randomly found an NPC named Septimus who sent me to a dwarven ruin to fill up some cube, starting a quest called "Discerning the Transmundane." In the process of filling his cube with ancient dwarven knowledge, I also found an Elder Scroll (!)

I gave him the cube, and I then got confronted with a Daedric Prince, leading me to believe that "Discerning the Transmundane" is a Daedric quest... Which is fine. However, there was something about all of it that seemed a bit like I might have jumped part of the main storyline. This is largely a hunch based on the writing of Septimus / the size of the dungeon / the eponymous object / etc. I basically want to check - without getting spoilers - if...

A ) This will cause some sort of bug when I do get around to the main quest (a constant worry for any wary TES adventurer)

or

B ) If I should wait on doing the next step of the quest (gathering elf blood) for any reason at all (ie, will completing this quest screw around with the main storyline in any buggy or non-buggy way.)

For what it is worth, reading the Elder Scroll seems to cause my character to have some sort of drug trip.

Probably just being paranoid, but I figured I'd ask. Thanks!

The Elder Scroll will become necessary later on in the MQ. Its ok to find it early - it shouldnt cause any problems.

Thanks!

I guess it is time to kill some elves and take their blood .

ok, but if you run into a sneaky looking bosmer dressed in nightingale armour, dont take her on! (its me!!)

Just avoid the twin sword wielding mohawk sportin' Redguard and you should be fine .

This might count as a Daedric quest (somone will be along who knows for sure), but

Hmmm... This complicates things. Anyone know for sure if the MQ is affected by finishing Discerning The Transmundane?

I just read the known bugs on Wikia and there is no mention of any of them affecting MQ.

Just make sure you keep a respectable distance from him at all times and let him finish his dialogues before talking to him or interacting with him or stuff...trying to be vague so as not to spoil anything.

Thank you buckom, I definitely appreciate the vagueness!

Thank you one and all for the feedback!

I don't know, as long as you keep the elder scroll you should be able to complete the MQ.

There's also a very nice place referred to as a bloodbank too, that will mitigate the crazy amount of time that can be involved with finding all the different Mer. It will give you everything you need, save for one type of blood.

It wasn't me...it was the guy at that place with the thing.

NP. I'm the same way: I come here to ask specific questions so I don't go past points of no return and don't want detailed walk-throughs on Wikia or UESP to spoil too much.

I did the exact same thing as you and found Septimus at about the same part if not a little before. I finished the entire Septimus quest before doing anything else with the MQ and everything worked out fine for me. Yes you will need the Elder Scroll later for the MQ but, at least for me, nothing messed up. I got the blood, finished the quest etc and went along killing dragons.

I completed this quest first before the MQ and both concluded ok.

Same here, getting the book was a priority because I'm a dirty cheater. No issues with MQ to report.
Just don't go killing people that aren't naturally hostile.

Hmm good to know this won't cause me problems later on then.
Septimus, I hardly knew ye.