Self-explanatory.

Mine would be:

Arch Enemy - Beast of Man
Mayhem - De Mysteriis Dom Sathanas
Immortal - Mountains of Might.

Three of my favorites would be:

Unanimated "Life's Demise" http://www.youtube.com/watch?v=1ohO-i73bzc

Naglfar "12th Rising" http://www.youtube.com/watch?v=_T1zWLgMLFY

Azaghal "Judaas" http://www.youtube.com/watch?v=HZVOnQuMuMc

those songs are really good, btw ^^^^

I'll have to put more thought into it to make sure I choose the absolute best in my opinion but, in recent memory, the chorus from Make Glorious the Embrace of Saturn by Anaal Nathrakh really stuck out for me as really really good.

I Am the Black Wizards. That song to me, along with De Mysteriis Dom Sathanas, is the absolutely definitive black metal song, and a big part of that song for me is the lead tremolo riff throughout the intro and first verse. Pure evil in musical form.

I remembered a couple more:

Misery Index - Angst Isst Die Seele

Emperor - Cosmic Keys to My Creations & Times

Honestly, as far as tremolo riffs of all genres go, my favourite would probably be the one in "The Price of Beauty" by Suicide Silence. It's heavy, it's fast, it's got a ridiculously memorable melody and it manages to make its point despite being extremely simple all-in-all.

Honourable mentions:

• Lykathea Aflame - "Bringer of Elvenefris Flame (0:54): Most of you know that I think Lykathea Aflame > all of you, so this was a no-brainer for me. It's pretty, it spirals upwards and finishes itself off with a little lick, then brings you back down just as calmly and peacefully. Like an angel picking you up and letting you taste the airs of heaven for just a moment before letting you return to Earth.
• N.K.V.D. - "Incipit SSSR": A pretty simple riff, consisting of only four different notes, but goddayum is it massive and catchy and just everything a riff should be! I might be favouring this one for N.K.V.D.'s production job more than the actual melody in the riff, but it still works about as perfectly as riffs can in this context.
• Portal - "Larvae" (3:15): Another fucking huge riff with a really ominous melody, practically sounds like it decomposes as it's repeated again and again. Reminds me of some monument slowly tilting and falling to the ground.

I might try to think of more later.

Well that is one of the better songs off the first Suicide Silence album. Sucks that the guitar tone on that album is so terrible that it muddles everything in that riff.

Enslaved - Eit Auga Til Mimir intro (then the verse). The whole song is killer but that riff which starts the song is so utterly brutal and well written!! probably the best riff on the entire Enslaved catalogue.

Gorgoroth - Satan Prometheus intro. It's classy, varied, well written and evil enough to be on par with the best material Infernus has ever written. Also, the harmonized section of the same riff later on the song sounds excellent.

Dawn - The Knell and The World, intro and chorus. The whole Slaughtersun album is full of great riffing, but those riffs are simply ripping.

Hypocrisy - Killing Art; both intro and here

For less known songs:

Varathron - Demoniac Abysmal Realms intro. Sounds both evil and 'hellenic'.

I Am The Black Wizards
En Vind Av Sorg
Transilvanian Hunger

Obvious but classic for a reason. And some newer ones:

Sargeist - Returning to Misery & Comfort (all of it, but if you know the song you know the riff I mean)
Funeral Mist - Jesus Saves! (the section before the ambient outro)

Both pants-shittingly emotional and awesome

Too many to choose from! Some of the ones that come to my mind first...

Belphegor's "Sanctus Perversum", The whole song is filled with some of the best tremolo riffs I've heard. It sounds evil, yet epic and majestic.

Horna's "Imperial Devastation", the main riff during the first minute or so. Much more basic than the previous one, but just as effective. That riff is to me the very essence of black metal, sounds evil and funebre yet strangely soothing.

Satyricon's "Nemesis Divina", I linked to the exact moment. The whole album is a classic of course, but that one riff I think is one of the best in Norwegian BM.

At The Gates' "Kingdom Gone". This is Melodic Death Metal done right, most of Eucharist's first album would also fit here.

I second this whole-heartedly

-Fornicationium Et Immundus Diabolus by Belphegor
http://www.youtube.com/watch?v=eiXk8tnaNTI
-With Satan and Victorioius Weapons by Marduk
http://www.youtube.com/watch?v=RrXh44Y4s5I
-The Secrets of the Black Arts by Dark Funeral
http://www.youtube.com/watch?v=vhnr62WBI4s
-Keravnos Kyvernitos by Rotting Christ
http://www.youtube.com/watch?v=gpm-yvWZZ5Q
-Final Ritual by Dark Funeral
http://www.youtube.com/watch?v=YkTu0J8hWCI

Lots of black metal songs in this thread so far. I'm going to contribute even more black metal by going with that awesome breakdown riff from "On Darkened Wings" by Marduk.

Cmon guys how has no one mentioned Mother fucking North?

http://www.youtube.com/watch?v=DD7bCRG3CG0

Oh yeh this one too http://www.youtube.com/watch?v=OTaWwEeG ... re=related

oh whoops. . .

Marduk - The Black... http://youtu.be/bVL0Pn74Ado (Opening riff)

Morbid Angel - Visions from the Dark Side http://youtu.be/lW-Zur-LcL8 (@ 0:23, actually, it's strange that nobody has mentioned this one before)

Dark Funeral- An Apprentice of Satan http://youtu.be/eJnKawXpM6A (@ 0:18)

Desaster - Tyrants Of The Netherworld http://www.youtube.com/watch?v=ZKLBpUj1r-4 (@ 0:43, epic as fuck)

Hellsaw - Dreams
Darkthrone - Transilvanian Hunger
Winterfallen - Fog In Thickets
Windir - Blodssvik

Eucharist - Floating immediately sprung to mind when I saw the thread title. The whole song is a journey, always with the energy to surge ahead, but when this part at 4:42 comes, it's a perfect break. The harmony that comes in makes it even better, and the song lifts to another level.

No one posted Dismember yet? Really?

http://youtu.be/L0ZCAarIVSI?t=30s

I also love the short one in Sodomy and Lust

http://youtu.be/jBXBRvHt8lg?t=1m38s

OK, let's stop with the retarded lists with no explanations or anything. If you can't discuss, don't post.

I really like the ones in 'Our Dawn of Glory' by Vinterland. They repeat that one riff for what seems like eternity, but the way they change up the rhythm behind it keeps it fresh and builds up tension for what's coming next. It beautifully establishes a feeling of longing and determination, and then when that second riff starts at 1:50, it sounds so epic and forlorn.

The riff at 1:18 is simply one of my favorites, is just so soothing but at the same time has an evil feel, I don't know, just love it.

http://www.youtube.com/watch?v=IbDttnRV62A

Darkthrone - Hans Siste Vinter and Burzum - Jesus Tod really gets me chubby.

Summoning - Land of the Dead and Drudkh - Skies At Our Feet are both tremelo masterpieces.

Never heard of this band before ^ but it's really good stuff.

Damn, that is a good riff. They could've repeated that riff a few more times and I'd be perfectly fine with it.

I found them both by accident. The music is so cold and mesmerizing and extremely addictive.

Evoken's Pavor Nocturnus is a favorite of mine. It's great to hear some low-register tremolo riffing and really compliments the build up of the track.

http://www.youtube.com/watch?v=A_kEB446sHU#t=8m06s

He must've been commenting the post above yours with Der Weg Einer Freiheit. Everyone, even Necroticism174, has heard of Darkthrone, Burzum, Summoning and Drudkh.

Alright, I'm going to hit a few really obvious ones here.

Behemoth - Ov Fire and the Void: Utterly demolishing and malevolent:
http://www.youtube.com/watch?v=TKWp_4358VE

Destroyer 666 - I am the wargod. Majestic and sinister at the same time:
http://www.youtube.com/watch?v=Ax7cdHiZ010

A few less obvious ones:

Behexen - Cathedral of the ultimate void - Perfectly captures the brooding, ritualistic sound of behexen, something that was lost on their newest:
http://www.youtube.com/watch?v=kVThZ_gCoeI

Demonical - March to Victory - The riff that kicks in right in after the first growl, hugely energetic and leads brilliantly into the pounding beat of the rest of the song:http://www.youtube.com/watch?v=nyWIVFkVMF0

Nifelheim - Infernal Flame of Destruction - The main riff is just face ripping; completely manic and unhinged. http://www.youtube.com/watch?v=wNQpd1W4sgY

Thanks for pointing me towards azaghal. Really awesome stuff. Also, if I like them and (early) behexen, should I look into horna? Is it more of that aggressive tremolo driven but melodic style?

I like your tastes quite a bit, sir

That middle part in Dissection's Thorns of Crimson Death is simply majestic.

It's diverse.
https://www.youtube.com/watch?v=TGo5Tgzlo6o
https://www.youtube.com/watch?v=73-JOhwcL2Q
https://www.youtube.com/watch?v=nV71PHVzLVo

The first song represents a minority of their output. It's from the second CD of Sanojesi Äärelle, which is about forty minutes of material quite similar to that. The second is some of the the grittiest Horna there is, from Sotahuuto. The last is from their first full-length, which could indeed be described as aggressive and tremolo-driven - melodic, but in a hateful way.

Horna's material that can most accurately be described as aggressive tremolo driven (but melodic) is some material from Envaatnags Eflos Solf Esgantaavne, early full-lengths as well as Hiidentorni demo, and some material on Sanojesi Äärelle. The single most appropriate song for that description would be this, in my opinion: https://www.youtube.com/watch?v=YxfxU0tsRNk . It's a cover of Pest(Fin) though.

This song is so great, how it builds up from slower part till the end. I used to listen to Estrangement alot to get asleep, I always waited for the ending blastbeat part of that song, it was so fucking ecstatic. Then I would usually fall asleep and the weird cannon (?) sound during "Where Horizons End" would wake me up in the middle of wonderful solo. Great.

I just have to mention this song: http://www.youtube.com/watch?v=NRRtbtT1odo - love that tremolo in the beginning.

Lots of favourites of mine already mentioned. I'll throw in these few as well:

Aldaaron - Royaume. (0:55) and (3:33 - 4:38)
http://youtu.be/LnYHy0uZcns Epic and even slightly uplifting. The rest of the album is filled with amazing tremolo picked riffs.

Apotheosis - The Maimed God (3:13 - 3:36) and (5:43 - 6:21)
http://youtu.be/t-q3uBA_1Pg Just plain evil. Best parts of the song and perhaps even the album, sadly.

Darkestrah - Sary Oy (10:10 - 10:45)
http://youtu.be/pkm1djybGbM Incredibly effective riff!

Forteresse - Honneur et Tradition (all riffs from 3:02 to 5:17) and the best at (6:10 till end)
http://youtu.be/-Wvp2my8ax0 this song for me is, next to Burzum's Jesus Tod, the epitome of black metal. Hypnotizing riff, distant and cold.

I've always had a few that will just pop in my head at random times and I always end up humming them. All of them are of a "classic" vintage (as am I). The one that first came to mind was Override of the Overture by Dismember, but someone has already posted that gem above. The others that have stuck with me over the years:

Possessed - The Exorcist: http://youtu.be/-YfOGtXz4wg?t=1m17s Kind of surprised someone had not posted that one yet. I remember hearing Seven Churches back in early '86 when a friends older brother played it for us. That was some scary music back in those days, especially for my 13 year old self who liked Maiden, Anthrax and Metallica. But it opened the floodgates to more extreme metal for me.

Sacrifice - Afterlife: http://youtu.be/zRPu6YB--D8?t=1m I bought Forward to Termination on cassette some time after it originally came out and I literally wore it out I played it so much. This song was always my favorite. To this day I will still randomly sing the chorus to this song. My wife thinks I'm crazy.

Hypocrisy - Life of Filth: http://youtu.be/hdHcYvBJIYg?t=10s I remember hearing this one originally on the Death Is Just the Beginning 2 comp, which was my first exposure to Hypocrisy. I think this song is on the re-release of Penetralia, but at the time you could only hear it on the compilation. I'm still a bigger fan of the first two records as I prefer Masse "Caligula" to Peter's vocals, but I'm still a fan of (most of) their catalog.

Igorrr - Tendon
http://www.youtube.com/watch?v=gWca1X7nFGo#t=2m35s
Not black metal so might as well be something you guys might enjoy. His music is messed up in a very good way.

Nachtwraak - Nachtwraak
http://www.youtube.com/watch?v=IuPrQG4Mq_w (Whole song!)

Luror- Smoke and Stardust
http://www.youtube.com/watch?v=ykEx_rOxmDw#t=5m53s
One of the best Suicide Depressive Riffs stuff.

Dawn (Swe) - Soil Of Dead Earth
http://www.youtube.com/watch?v=HdBubQ5tN64#t=4m35s
This riff, is what got me into bm in the early days. It's really christraping pure fucking win.

Hinsidig - Bak Livets Forheng
http://www.youtube.com/watch?v=DuvBaLJ3dJA#t=3m40
One of the lesser known but amazing atmospheric bm bands.

I don't know how known are the bands above (except for Dawn) but I hope someone will appreciate them as much as I do, because I didn't want to post obvious good riff bands which are more known (i.e. Taake)

It is right? Der Weg has become one of my favorite black metal bands pretty easily.

Another one that I really like:

Akercocke - Verdelet (at 2:19)
http://www.youtube.com/watch?v=gx4jaqmTVRE

For death metal, Dead Congregation's "Graves of the Archangels"
The link is at the right moment: http://www.youtube.com/watch?v=jT9vxYGqyWI#t=1m48s

For black metal (aside from songs like Mother North that have been mentioned already):
Rotting Christ - "The Sign of Evil Existence" http://www.youtube.com/watch?v=SExkSsD6y3M#t=33s

I don't know why I love it so much. It isn't even that great a riff. But we Greeks still go batshit crazy every time RC or a different cover band play it on stage.

Is tremolo picking used much in non-extreme metal? I know a bunch of speed metal bands have used it, but I'm having trouble thinking of an exact example.