Why Death Knight should not get buffed.

People who want DK buffed are not realizing this class has 5 expansion and 4 minisets less cards than every other class right now. 

Not to mention it would probably break arena.

Buffing DK also wouldn't help it against any more decks really, it would just be even stronger against the decks it's already strong against or it just become extremely busted to the point where Blizzard just has to go back and nerf it after the buffs. 

DK may need some tweaks but not straight up buffs. If they're gonna buff it they need to nerf some problem cards as well.

For example Patchwork should not be a 1 rune card.

Instead of buffing they could just use the miniset to add some support to the class, DK is lacking in cards not strength. 

It really doesn't matter how many cards the class has. Team5 is responsible for the power level of the class, whether or not the class has ten or a hundred less cards than other classes doesn't even factor into the conversation. There's tons of cards that dont ever see play, and specifically classes like warrior might as well not even exist in the current meta.

But I do agree that DK doesn't need buffs. And the reasoning is fairly straight forward. Their cards are busted for their cost already. Heart Strike is a 1 mana deal 3, where the standard being 2 mana for the same damage. Vampiric Blood gives 10 health and draws a card for 2 mana. Boneguard Commander summons a board full of 1/2 taunts. Frostwyrm's Fury is straight out busted. But to answer the question as to why DK isn't doing well despite all these cards is simple;

- The rune system, as I opined a month ago, doesn't encourage better deckbuilding it simply restricts each archetype to their respective runes and disables interesting interaction (and thus interesting deck building). Imagine if I could play a frost deck that can actually decently control, or gain corpses. Or if I could insert a few niche cards into blood control like Horn of Winter etc. Instead, all we get is the standard blood, frost etc. deck that's really not much different from what team5 themselves came out with. So there's really a dearth of options.

- DK draws like shit. In a world where your class draws worse than every other class other than warrior, you're really not going anywhere. Hence why warrior themselves are currently shit too. I mean, we used to poke fun at priest for this and suddenly that class can draw their whole deck now.

- The pop off turns of the current meta is nuts. Turn 4 12/12 draka weapons, etc. DK is simply not fitted to deal with any of these. Or indeed most classes as a matter of fact. That is why the solution is not buffing DK, its toning down the obvious bs the other classes are doing.

Besides, DK is doing very well in arena. I think that alone shows how much pumped up their cards are, when the meta isn't putting out 12/12 stealth minions on turn 4. I think when the meta is more 'fair' then DK will come out on top, and get inevitably nerfed because their cards are power creeping existing standards as it is.

I would prefer team5 to remove the rune system and balance DK's cards. But this is obviously never going to happen.

Agreed, no DK buffs please. My two cents:

• The corpse mechanic while fitting flavor-wise is largely redundant; in theory this should place a further restriction on cards and limit the overall power level, in practice I find this seldom to be relevant at all (apart from making some generation and thief mechnics much worse for the non DK opponent)
• Arena: Arena is my main game mode and it is in one of the worst states I can remember; it's basically draft DK or go f*** yourself; above 5-6 wins is DK territory; my personal win rate against DK with non DK classes is maybe 20% and I am a fairly experienced Arena player
• Rune mechanic seems restrictive and unfun; again I feel this was designed to fit flavor-wise but not gameplay-wise

That being said I don't expect any meaningful changes coming soon.

You're all making some valid points but at the end of the day, the class isn't competitively viable. It's really a shame, not a single DK deck was brought to the world championship! Cards may be busted but the decks don't work as well as others. So I don't mind some buffs here and there.
Obviously these don't have to affect the already strong cards, but boosting the class by improving the some of its average cards seems fine to me.

Runes are indeed part of the reason, decks didn't take off. But they surely won't scrap that mechanic, even though it was way to ambitious from the beginning. All archetypes have to be strong, otherwise they are just dead cards. It essentially splits the class in 3, further reducing the chance of viability of different deck types. I don't see any benefit in that.

Arena is a problem for buffs, but thats ane entirely different story and will mostly be fixed by offering rate adjustments and maybe some bans.