Not altogether bad. Intertwining the original and your translation for ease of comparison:
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Alduin's wings, they did darken the sky.
Alduin's viingge nust drey vul faal lok
His roar fury's fire, and his scales sharpened scythes.
Rein nah yol ahrk qah kinzon tuzze
Men ran and they cowered, and they fought and they died.
Muz ru ahrk nikriin ahrk grah ahrk dilon
They burned and they bled as they issued their cries.
Nust ag ahrk saansil ol nust komeyt nust zulle
We need saviors to free us from Alduin's rage.
Mu laan saviik wah stin mu nol Alduin's ruth
Heroes on the field of this new war to wage.
Hunne nau pindaar dodaar kein wah win
And if Alduin wins, man is gone from this world.
Ahrk fod Alduin kronne, muz los vod nol daar lein
Lost in the shadow of the black wings unfurled.
Sizaan kofaal vokun dofaal ved viingge fundein
But then came the Tongues on that terrible day.
Nuz ruz bo faal Strunzul nay tol maar sul
Steadfast as winter, they entered the fray.
Fenmul ol fin evgirkrah, nust aav faal kein
And all heard the music of Alduin's doom.
Ahra pahmuz hon faal lovaas do Alduin's daanik
The sweet song of Skyrim, sky-shattering Thu'um.
Faal lovaas do keizaal, lok kren Thu'um
And so the Tongues freed us from Alduin's rage.
Ahrk ful faal Strunzul stinmu do Alduin's ruth
Gave the gift of the Voice, ushered in a new Age.
Kogaan ofan do faal Thu'um, drun ko faal rus bok
If Alduin is eternal, then eternity's done.
Rul Alduin's unslaad, rus ulis lost gutvod
For his story is over and the dragons are gone.
Fah oktey los ko, ahrk faal dovah los vod
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Faal Strunzul is very good for "The Tongues". Immediate grammar and spelling points:
- saansil, dodaar, kofaal, kodaar, fenmul, stinmu, ulis and oktey all look like two canon words run together. It's unclear in context if they are compounds or typos. Also, there exists a canon word sosaal "bleed".
- You leave the English possessive clitic ('s) untranslated. Is there a reason for this?
- Kron "conquer" is a verb and thus cannot become plural. Kronne does not exist.
- Daanik "doomed" is an adjective. You want daan "doom" instead.
- Ok tey los ko means "his tale is in(side)". For the idiomatic English meaning of "over", use vod or oblaan.
