"Dragonrend" simply is a descriptive label of the thu'um that comprises of the words "Mortal", "Finite", and "Temporary". Obviously, this has a highly disruptive effect on the concentration of the dragons, as mortality is as incomprehensible to them as eternity is to a mortal.

But what if it were shouted at a Daedra? I'm not talking gameplay technicalities... Would it have a detrimental effect on daedra as well? Like dragons, they are eternal beings too.

I'd vote "probably". Dragon souls are affected by temporal distortions (Dragon Breaks), because they exist outside of time. On another note, they're (probably) splinters of aedra, who are dead gods. Aedra are only dead in the sense that their corpses comprise Mundus. The only difference between aedra and daedra is that while aedra are the dead "bones" of the world, daedra are the spirits who aren't part of the world, but have an interest in it. My arguement is really bad, because it basically boils to A=B, B=C, therefore A=C. Dragons=aedra=daedra...sorta. Long story short, daedra are immortal in the sense that they don't reincarnate but can be slain like dragons (lose all their sense of self in the dreamsleeve, unlike mortals), so I'd reckon that Dragonrend would hurt them.

I wouldn't expect it to. The shout is powered by hatred of the Dovah, so it is likely to be useless against Daedra. I suppose its possible, though. Like Alkeno said, they come from similar stock. But then again, so do mortals. They're just further down the "family tree", so to speak.

It's already known that daedra know what death is, and comprehend it, but do not fear it.

M'eyap wants to shout, too!
DINOK-VIIK-FAAS! Ho, M'eyap just learned a tu'um that banishes the evil Daedra!

DAH-TIID-DAAL! Ho ha ho, Dar-Oska just made a khajiit forget his new combination.

I wonder. It was made to force the understanding of mortality, which Dragons cannot do. Daedra, since they do "die" to a degree and have to get a new body entirely rather than have their old one rebuilt, can understand death even if on different terms than humans. So I think if anything it probably just feels weird.

"I think someone's spiked my flin" weird, or "I just read Sermon 14 of the 36 Lessons of Vivec and have to bathe" weird?

Dunno, maybe both. Or a sort of weird we don't have and therefore never bothered to name.

Draconic has power because its users are fundamental parts of mundus and thus their language has power over mundus, but as they are part of mundus the language also has power over them. Daedra, being separate from mundus, cannot be influenced directly by this power like the dragons that are bound to mundus. So a shout like dragonrend that is directly targeted at influencing an entity would not work on a daedra because they are separate from the system the shout acts in.

I don't know about this. Thu'um is just the traditional Nordic brand of magic. And magic operates perfectly well in Oblivion. I don't believe there is anything special connecting it to Mundus.

Well it's not like magic, actually. They call it that because it's "the lie we'll understand." Magic is bending the energy of aetherius to your will. The thu'um is taking the energy of your own spirit, represented by air/breath and therefore linked to Kyne, and enforcing your will upon the world with words the way people influence the gods by belief. So maybe it will work in Oblivion or on Daedra, but then again, Kyne is an Earthbone, and linked to Mundus that way.

So maybe it could mess up the thu'um to be in Oblivion or to try to tamper with a Daedroth mind, even though obviously combat Shouts work on Daedra who are on mundus.

I figure it'll probably work. After all, magic in the planes of Oblivion don't require Magnus to be nearby (and I'm assuming that the Shivering Isles sun isn't Magnus).

i would make a different assumption - that the sky behaves similarly in oblivion planes to the way it behaves in mudus in that it is separate from that realm. if magnus shines from aetherius through the void of oblivion and all the way to mundus then it probably hits the planes of oblivion in the same way.

Well the other stars also emit magic in the same way. I wonder if a different Magna Ge ripped open the stars that the daedra lords choose to keep their realms close to in order to steal the leaking magicka to enhance and build up their own realms?

Somebody go back and mod oblivion so you play as the Daedraborn and you use shouts to absorb the souls of Daedra, then Daedrarend MD at the end of the MQ, you kill him ... but don't absorb his soul...

But the Planes of Oblivion are much further away from Magnus than Nirn is. It'd appear as any other star from that distance.

Regarding the Voice, I'd say that given its power can go beyond what the Dragons can comprehend (as evidenced with Dragonrend), I figure it's not restricted by the borders of Kyne's or Akatosh's influences. That said, the Daedra probably wouldn't be affected because they understand the concept of mortality. If anything, a Daedrarend would probably be something along the lines of why mortals do not despair despite their finite, mortal existence.

In seriousness though, assuming at least one DLC is going to be Daedra based, I'd like to see some Daedra specific shouts. I can't seem to find anything on user's of Thuum interacting with Daedra, with the exception of the Quests in Skyrim.

Waaat. Oblivion envelops the Mundus, does it not?

Yes, in a manner, but the realms of Oblivion are imitation-spaces that occupy the great "sea" of Oblivion itself. When people say that the stars and sun are holes in Oblivion to Aetherius, they don't mean like a pinprick in a curtain. Or, well, they actually do but it's more than that. The hole is viewable from every direction, see, so you can be standing on opposite sides of the hole that is a star from someone and yet still both be in Oblivion, and you can both enter into the same hole from any direction.

At least that's how I've figured it's supposed to be, based on the way the sky looks whenever we see or have described a Daedric plane(t).

mundus is at the center of the wheel of the aurbis. oblivion surrounds it and aetherius surrounds oblivion. depending on where the plane floats in the void it could be closer to, farther from, or the same distance from the sun as mundus.

I'd imagine a Magna-Ge sized hole would look pretty big up close, perhaps say Sheogorath's shivering isles is next to the hole he tore through when he was fartin about in the Mantellan crux that time.

Or meridia's realm is located next to the hole she left through then was cast out from...

Oblivion does envelop the Mundus. But the voids of Oblivion and the planes of Oblivion are not the same thing.

But which sun? Magnus is clearly closer to Nirn than the other stars, it's not just a larger hole on the inside of a sphere (also note that it was not represented in the Orrery). In addition, the layout of the stars appears different in the Shivering Isles.

ok, which model of the aurbis are we going by? i'm referring to Cosmology which says all the stars are equidistant from mundus and magnus is just the largest whole. is there another model that's more reliable?

Magnus is probably the largest, but why do they have to be equidistant?