Classical Music flavoured like Oculus Ex Inferni?

Carl Orff - Carmina Burana: Oh, Fortuna

Dies Irae & Confutatis parts of different composer´s Requiem´s,
like e.g. Verdi´s Requiem, Mozart´s Requiem

Parts of Gustav Holst - The Planets: Mars the Bringer of War

Parts of Batman soundtrack, Main theme ;)

Otherwise, for the same kind of variation in the progress of a classical piece, look for classical composers from the Romantic era, writing program music. (music with a story or other non-musical relation.)
Mussorgsky - Pictures at an exhibition...
 
Your welcome!
Ah, and some other movie soundtrack composers, of course.
Hans Zimmer, and other big picture movie score composers.

Movies like Lord of the Rings, and other clear Good vs. Evil movies...
 
As of right now, I can't remember anything he's done but surely John Goodman is also guilty of creating something in that style? I'm sure he'd be easy to chase up!

LOTR has an AMAZING sound track. That 5/4 piece they do at Orthanc is amazing.
 
3/4 of Underworld by Adagio, only it's slightly less guitarry and a lot more odd time signaturey
 
There's some awesome music on Vangelis' "Mythodea" release. The first movement, in particular, kicks ass. It just builds and builds in power and intensity until the climax. The whole album has some incredible music ranging from slow, atmospheric melodies to thunderous pieces. Definitely worth checking out.

Other grand/epic pieces you might like are "Requiem for a Tower" by Clint Mansell (based off his piece "Lux Aeterna" from Requiem for a Dream)

"Roll Tide" from the Crimson Tide soundtrack

"Liberi Fatali" from Final Fantasy VIII. Amazing track.
 
Solvet Saeclum In Favilla; yeah the choir in that is what made me realize that Forte knows his shit as a composer.