I'll come right out and say it: I'm (now blatantly) copying obsidiandice's Oros thread. I never considered just posting a deck for reference, and the deck was already built and working by the time I joined the forums. This is one of my better decks, if not my best, and the one I pull out for revenge. Comments and advice are still welcome.

General:
Karrthus, Tyrant of Jund

Creatures: 22 with Karthus
Artifacts: 0
Enchantments: 4
Planeswalkers: 2
Instants: 14
Sorceries: 20
Lands: 38

Dumb Beats: 10
Deadly Recluse
Bladewing's Thrall
Sek'Kuar, Deathkeeper
Homura, Human Ascendant
Hellkite Tyrant
Kokusho, the Evening Star
Dragonlair Spider
Dragon Broodmother
Utvara Hellkite
Hellkite Overlord

Removal: 20
Flayer of the Hatebound
Malfegor
Thunder Dragon
Balefire Dragon
Bogardan Hellkite
Sarkhan the Mad
Sudden Shock
Terminate
Rakdos Charm
Golgari Charm
Savage Twister
Clan Defiance
Krosan Grip
Beast Within
Putrefy
Maelstrom Pulse
Lavalanche
Sever the Bloodline
Creeping Corrosion
Blasphemous Act
Plague Wind

Recusion: 12
Eternal Witness
Bladewing the Risen
Reanimate
Victimize
Makeshift Mannequin
Torrent of Souls
Beacon of Unrest
Living Death
Patriarch's Bidding
Cauldron Dance
Animate Dead
Necromancy

Tutor/Draw: 12
Mindclaw Shaman
Valley Rannet
Igneous Pouncer
Knollspine Dragon
Faithless Looting
Wheel of Fortune
Buried Alive
Jarad's Orders
Reforge the Soul
Tooth and Nail
Survival of the Fittest
Greater Good

Other: 7
Anger
Garruk Wildspeaker
Blades of Velis Vel
Skullcrack
Moment's Peace
Delirium
Sudden Spoiling

Land: 38
Mountain, 7
Forest, 6
Swamp, 7
Terramorphic Expanse
Evolving Wilds
Wooded Foothills
Taiga
Badlands
Bayou
Raging Ravine
Gruul Turf
Rakdos Guildgate
Rakdos Carnarium
Golgari Guildgate
Golgari Rot Farm
Vivid Crag
Vivid Grove
Vivid Marsh
Savage Lands
Command Tower
Boseiju, Who Shelters All

Being a dragon deck, the creature curve is more of a plateau. I spend my early turns stting up lands, killing creatures where necessary, tutoring, and/or mabye playing a planeswalker. Midgame, I play dragons. Mid-late game, I rez dragons. Despite my terrible description of the mid-late game, it's fun to play with some neat interactions, like Inferno Titan/Bogardan Hellkite+Virulent Swipe, Tooth and Nail+certain dragon pairs (with the real interaction being between the dragons), or Blades of Velis Vel+Karrthus (after he hits play, but before his ability resolves).

This is the only deck I run that's so low on non-creature permanents, but it works out pretty well. With only 4 cards a naturalize can target, artifact/enchant destroy is mostly a dead card, or directed at other opponents' stuff, saving me resources. With few non-creature permanets and plenty of recursion, sweeps are much less effective against Karrthus than any of my other decks. It also doesn't have any ramp, which might be weird for a dragon deck, or any deck with green, but I get my mana just fine.

Whoah! Blades of Velis Veil is some sweet secret tech for Karrthus. I'm shamelessly stealing that one, but the only problem is that my friend (i.e. my opponent!) is the only Karrthus player, so now I have to debate with myself if I actually tell him about it. I'm usually the guy who is more than happy to help tune up someones deck, even if they're going to beat me with it! But Karrthus is already his best deck overall, so I don't know that it NEEDS more help.

Shamelessly steal whatever card choices you want from me, just tell me so I can think I'm super cool for using them. I would advise that you not tell your friend, but if it were me, I would definitely tell your friend. Those creatures are yours (well, his), pumped, and ready to swing.

Blades is cool tech in a dragon deck.

Are you going to try Death By Dragons?

I'm in the process of building a new deck around Karrthus, so this will come in handy for some ideas. Did you consider cards like Dragonmaster Outcast, Dragonspeaker Shaman or Crucible of Fire? I also plan on playing Mana Flare and the green version of the mana flare (can't remember the name right now).. I figure a lot of my stuff is pumpable so I don't care if it benefits my opponents too, they'll be stronger for me. Thoughts?

Mana Reflection?

Heartbeat of Spring is the one I meant. I also thought about Vernal Bloom but I don't think that would help me as much as green is more of a splash color for me.

Death by Dragons--Probably going to replace Broodmate Dragon, but definitely going in. It seems like good fun, even without stealing them all. If I get lucky, it'll be 4RR + rez mana (targeting Karrthus) to have a hasty dragon for each opponent. I am so excited for death by dragons.
Dragonmaster Outcast--It looks nifty, but I don't think it's that great. My problem with it is that it doesn't work until turn 7ish, by which point, almost anyone that wants to can take out a 1/1 that makes dragons. I haven't used it, so people that have may decide I'm wrong.
Dragonspeaker Shaman--I was lucky enough to pick up some Urza's Incubators before I knew the price (which were over $6 when I first checked, way back), but even those didn't make it in. Initially, I just didn't care about the price of these guys, because I would just rez them. Writing this out is making me reconsider the incubator. Dragonspeaker really stands out as a target to people. The last time I let one live, a Kilnmouth killed me.
Crucible of Fire--I think it's a win-more card. Unless you're pumping out dudes with Dragon Broodmother, then you really should have it. Speaking of broodmother, if you run her, try Bladewing's Thrall. Just throwing that out there for people who haven't thought of it. It's something I keep coming back to with Karrthus, as if it was seasonal.
Mana Flare/Heartbeat of Spring/Mana Reflection--Mana flare and the like kick ass in other decks, just not mine. I had all of them in the deck, but I was never super excited to see them. This deck always worked well without mana accellerators and they kind of got in the way, since I could be drawing a business spell or a land, which is better than a mana rock if you would otherwise miss a land drop. It even led to me filtering out most of the non-land, non-creatures permanents. It's also why I think my deck is weird compared to other builds.


Splash or not, vernal bloom is crap in a 3-color deck.

I see your points on those cards. I put my deck together tonight with the cards I already have. I'm sure I'll make some changes to it in the near future, but this is my current build.. and I plan on playing it tomorrow night. I'm open to suggestions on how to improve it.

Commander:
Karrthus, Tyrant of Jund

Creatures:
Darigaaz, the Igniter
Steel Hellkite
Malfegor
Kaervek the Merciless
Geth, Lord of the Vault
Inferno Titan
Dragonmaster Outcast
Galvanoth
Urabrask the Hidden
Ryusei, the Falling Star
Magma Phoenix
Moltensteel Dragon
Furnace Whelp
Hoard-Smelter Dragon
Ancient Hellkite
Mordant Dragon
Scourge of Kher Ridges
Hellkite Charger
Shivan Dragon
Shivan Hellkite
Hoarding Dragon
Shivan Phoenix
Hellkite Overlord
Broodmate Dragon
Bogardan Hellkite

Enchantments:
Leyline of Punishment
Electropotence
Mana Flare
Where Ancients Tread
Crucible of Fire
Phyrexian Arena
Heartbeat of Spring
Khalni Heart Expedition
Oversold Cemetery

Artifacts:
Nihil Spellbomb
Sensei's Divining Top
Sol Ring

Planeswalkers:
Sarkhan Vol

Instants/Sorceries:
Banefire
Red Sun's Zenith
Slagstorm
Earthquake
Ricochet Trap
Assault Strobe
Reverberate
Elemental Appeal
Shatter
Crush
Creeping Corrosion
Deconstruct
Cultivate
Dismember
Grasp of Darkness
Go for the Throat
Doom Blade
Disentomb
Rise from the Grave
Grim Discovery
Morbid Plunder
Demonic Tutor
Plague Wind
Blades of Velis Vel

Land/mana sources:
Raging Ravine
Rootbound Crag
Kazandu Refuge
Vivid Grove
Evolving Wilds
Terramorphic Expanse
Verdant Catacombs
Akoum Refuge
Firewild Borderpost
Rupture Spire
Ancient Ziggurat
6 Forest
9 Swamps
14 Mountains

Bad cards (or so I think):
Shivan Phoenix--I think you can do better for 6 mana, because it's not very powerful. It's just resilient. If you like the resiliency, try out Darksteel Gargoyle. Otherwise, find the nearest dragon that's not in the deck, and put it in.

Elemental appeal--You can do better with 9 mana. So much better. It's a one-shot that might not hit. You could run X spells and Exsanguinate for 7, or Lavalanche for 6, or Dragonstorm, or...*rambles on*...or Comet storm for 7/6x2/5x3/4x4. I guess, really...I just dislike elemental appeal.

Shatter/crush/deconstruct--There's nothing wrong with shatter effects, but you can get much better: Ancient Grudge, Artifact Mutation, Fury Charm, Hull Breach, Shattering Pulse, Smash to Smithereens, Shattering Spree (replicated), Manic Vandal, Vithian Renegades, and Aftershock. Better than most of those cards are Naturalize and Krosan Grip. In your colors, green is the only one that can ace enchants, so you should make use of that. You seem to like Disentombing, so getting these effects from creatures (like acidic slime and Indrik Stomphowler) would be even more beneficial.
/bad cards.

Grasp of Darkness is good, but Sudden Death is great. 1 more mana for split second.

Bladewing the Risen is an auto-include for Karrthus, as far as I'm concerned. It comes in heavenly inferno, so even if you don't buy it, you'll definitely have the opportunity to trade for it. Same for Mana-Charged Dragon.

Past that, you're going for a defferent kind of deck than me, so I'd have to hear about how tomorrow night goes before I could suggest anything else.

Some nice choices in the deck, the Blades of Velis Veil is really cool tech like others said.

Some cards that seem week to me:

Rise from the Grave - Beacon of Unrest is definitely an update

Igneous Pouncer + Valley Rannet - Even with reanimate you would be better of with some green ramp I think. Sakura Tribe Elder, Farseek, Kodama's Reach, etc.

Greenseeker also seems rather week, it can be a discard outlet I see but it still seems to be a bad draw most of the time.

Xira Arien is to slow and requires to much mana to do something. You have acess to much better draw. Phyrexian Arena or Chandra Ablaze (wich can also play as removal and/or discard outlet) come to my mind.

Also Jund Panorama seems better than any etbt-land.

Rise from the Grave--My lone beacon is busy elsewhere. It's tough having multiple decks that want to rez stuff. I'm just glad Chainer does his own rezzing.

Igneous Pouncer/Valley Rannet--This one's tough. I can't argue with you about those being solid choices, but I think I'm just stubborn (they don't sit right in this deck, even though they're auto-includes in other decks), and my deck hasn't shown a need for them. Pouncer and rannet are my extreme mana fixing, grabing what I need regardless of what I have available, and I do rez them sometimes, so beef helps.

Greenseeker--A bit weak, I agree. It does it's job well enough when I manage to see it, and it's not a big target for others, but I don't draw it much, so it could probably come out.

Xira--Yeah...It's kinda bad. I like it, but I haven't so much as drawn it since I put it in, so I can't defend it. It could come out.

Jund Panorama--If I want to pay mana to make a land tap for the color I want, I'll run Rupture Spire. Panoramas have only disappointed my in the past and I won't use them unless I'm desperate.

Updates to the list that I forget:
Desert Twister-->Beast Within
Stitch Together-->Reanimate
Arid Mesa-->Lavaclaw reaches
I'll probably update it again later with:
Broodmate Dragon-->Death by Dragons
Xira-->Mana-Charged Dragon
Greenseeker-->Sudden Shock

The dragon stuff is clearly good, as long as I can fit them. Sudden shock, I've been wanting for a while, so I could ace some little control dudes right in their little control faces. Like Momir Vig, or utility dudes like Lyzolda. Or to finish off an unsuspecting creature when my opponent has his guard up.

Rollcage.. thanks for the advice. The deck was put together with the cards I had on hand (and a few that I just ordered). I'd agree with your opinions on those cards, most of the suggestions you made I was not even familiar with but now gives me some options to explore. The one I can't believe I didn't put in was Naturalize. That should have been in there in place of Shatter or Deconstruct. Fury Charm I do have on hand and will make the swap immediately.

Well, I got to play 2 games with my deck tonight. The first game I got off to a very good start ramping up my lands so that I had 8 lands into play by turn 5 I believe. Got my commander out. One of my opponents promptly cloned him, killing him. Then the next guy destroys all lands. Hmmm.. the rest of the game didn't go so well.

Second game went much smoother though and I easily won. It was 4 person FFA by the way. I was able to play Where Ancients Tread and Dragonmaster Outcast on turn 6. Nobody had an answer for it for 6 turns. So, I laid down some fatty dragons during my upkeep and played an additional dragon from my hand each turn, all while destroying any creature threats on the board. By the time someone killed my Dragonmaster Outcast I had 8 5/5 dragons on the board, and a Crucible of Fire in play. Needless to say the game didn't last too long after that. I was happy overall with the deck, but I did pick up a handful of the cards you suggested and a Sarkhan the Mad

Game 1--At my table, I'm the one most likely to clone, so I don't have to watch for that so much. It sucks when it does happen, though. Kill my Karrthus And steal my dragons? Uncool, dude.

Game 2--Grats, man. No answers for six turns is impressive. You've just convinced me to try where ancients tread. In the final three turns of the last game I played with Karthus, I could have triggered that seven times. If I do, I might try to run Dragon Broodmother and Bladewing's Thrall again, to trigger it every upkeep.