Well not necessarily Armageddon, but i'm mostly talking about a sense of impending doom, of a great disaster being visited upon a large area.. this can refer to:

-global divine apocalypse
-nuclear holocaust/fallout
-total destruction of a city/country/whatever(kind of like the myth of Sodom and Gomorrah)
etc

imo the 2 songs that give the best feeling of something like an Apocalypse are

-Amon Amarth - Death in Fire. it has this impossibly epic and doomy sound, it's about the Ragnarok or basically the Norse version of the Apocalypse, few songs come close to this in how atmospheric and evocative the riffs are, they simply ooze divine flaming destruction raining from a red sky on the whole earth.

-Dark Angel - Darkness Descends. while the riffs aren't as atmospheric as on the former, the incredibly vicious vocals and the breakneck (literally) speed of it all pretty much give a sense of total destruction taking place, and you're right in the middle of it and can't escape. brilliant.

I would have to say any Anaal Nathrakh song, especially some of the ones off their album soon to come. I believe they've been refered to as Apocalyptic BM before?

Anything by Anaal Nathrakh, or V:28!

.:crast:.

Anaal Nathrakh's whole last album. Kind of soundrtack for apocalypse.
And Dagoba has some really apocalyptic songs both in lyrics and in the feeling.

In addition to what i said before, 1349 has aome apocalyptic sounding songs as well.

Does Armageddon by Gamma Ray count?

The first song that came to my mind was Damien by Iced Earth. It may not be the heaviest song ever, but I think it fits here perfectly. I'll think of others and post later.

Vetustas -Ragnarok

Withstand The FALL Of Time by Immortal. Epic.

You all, go check "Stones From The Sky", and then tell me it's not the best apocalyptic song ever written.
That said, I also like a lot Dark Tranquillity's "Inside The Particle Storm"

Armageddon Anthem by Zonaria, both lyrics and music are very exploded

Wow I totally forgot I created this topic

anyway the first song that came to my mind were Amon Amarth - ...And Soon The World Will Cease To Be. just awesome and apocalyptic, and probably AA's most epic song.

Kreator - When The Sun Burns Red. Masterpiece:

Savage heat is searing
Global warming has begun
Mother earth is reeling
No protection from the sun
Forest fires are raging
While the rivers turn to ice
Foolish man creating
Mother nature's cruel demise

Hailstorms, tornadoes
Cold spells, untimely frosts
Heat waves and blizzards
Global death's the cost

face the end of time
as we plunge headlong towards the day
can't deny the signs
when the sun burns red
the earth will turn
from blue to gray

winter turns to summer
then the seasons disappear
no one needs a prophet
to explain what's all too clear
oceans overflowing
islands drowning everywhere
leaders wouldn't admit it
now they're crying in despair

hailstorms, tornadoes
cold spells, untimely frosts
heat waves and blizzards
global death's the cost

face the end of time
as we plunge headlong towards the day
can't deny the signs
when the sun burns red
the earth will turn
from blue to gray

now rain shall wash away sad remains of man
cities once so proud will crumble in sand
buildings collapse when all is done and said
the guilty ones will die with the innocent
when the sun burns red

Hammer Smashed Face would aid in the destruction of a City, but for Fallout?

That's a toughy...

Onslaught - The Sounds of Violence
Accept - Hellfire
Also something by Vektor, maybe Accelerating Universe?