Simply stated, the side that has the highest concentration of Death Knights will inevitably be the victor.
Arathi Basin. Horde has two Death Knights. Alliance has five. The Alliance will win.
Warsong Gulch. Alliance has one DK. Horde has three. Horde wins.
Eye of the Storm. Alliance has seven Death Knights. Horde has one. Alliance wins.
And on and on and on…
The only possible exception to this may be Alterac Valley, I don’t know; with queue times measured in hours it’s difficult to test.
Nonetheless, it seems to hold true for everything else.
It seems to be restricted to Unholy Death Knights, however. Frost and Blood don’t seem to count towards this theory.
Played an AB with each side possessing three DK’s. One of the alliance Knights was Blood specced. Alliance lost. All of the Horde ones, of course, were Unholy.
Death Knights aren’t particularly invincible, just very difficult to fight. They possess a very high number of powerful cooldowns, and exhibit zero hesitation in using them. As such, the only response is to use your own cooldowns, and if multiple Death Knight’s are present, it’s only a matter of time…
It’s a war of attrition. A war the Death Knight’s always win.
They wear plate, hence physical DPS is restricted against them. A substantial amount of their damage comes from Magic damage, rendering heavily armoured targets largely moot against them. The number of tools they have to mess up casters and healers is greater than any other class.
On top of that, they need to be killed twice and have a permanent pet in roughly the same boat as a hunter’s, and can even summon a second one, or a whole bunch of them every twenty minutes.
Speaking of which, being on the receiving end of six simultaneous “Army of the Dead” is a lesson in true terror. WTB Ret Pally.
The issue with multiple Death Knight is that they don’t even have to be organised to be incredibly dangerous. A group of, say, three Death Knights can throw themselves into a group of enemies, mash random keys while pressing tab and deal unmatched catastrophic damage.
Consider a group of people defending Lumber Mill. Some Death Knights attack.
The mage gets Death Gripped, blinks away, and is immediately snared. The priest can’t help, as he was just silenced. The mage attempts to kite the DK, only for the DK to render himself immune to all magic.
A rogue attempts to assist, but is broken out of stealth early by a DoT of some sort. Don’t ask which one, there’s, like, seventy billion DoTs flying around whenever DK’s are involved.
The priest just got Death Gripped. A Warrior wades in, only to sadly watch his health bar drop faster than the opposing DK. The mage just got hit with Mind Freeze. The rogue can’t Vanish, too many DoTs.
The mage can’t DPS, the DK tossed up an anti-magic zone. And then got silenced again. The rogue attempts to flee, blowing Sprint to try and get some distance. Chains of Ice.
Eventually, they kill one of the Death Knights, who promptly resurrects himself as a zombie and continues to attack.
As time drags on, the opponents of multiple Death Knights get run down. It takes an inordinate amount of effort to kill a single Unholy Death Knight, and when dealing with large numbers of them, it just takes far too much time to bring them down.
Slowly but surely, they inevitably win.
Think about it this way. Even one DK can cause a lot of damage, simply by harassing a healer. Snares to prevent the healer from fleeing, thus forcing them to heal themselves, or attempting to dispel themselves. They can be silenced, Death Grip interrupts spells, and when they finally get the opportunity to cast a spell, they’re hit with Mind Freeze.
For this entire time, the healer isn’t healing. All the other teammates are still taking damage, it’s just now there’s effectively no one to get their health bars back up.
The healer, then, is restricted to instant cast spells and HoTs. Slowly but surely, they fall behind. Meanwhile, disease is on sale and everything must go!
Picture a zombie horror movie. Any will do. The hero’s have plenty of guns, food and water. No problem.
Except… there exists a limit to the ammunition. If a guy has a rifle and five thousand bullets, that means he can kill five thousand zombies if he never misses and always gets a perfect headshot.
If he’s fighting six thousand zombies… well, I’m sure we can all guess how that ends.
As of yet, the only viable counter I’ve found so far is to have a powerful offense at the beginning of the battle to quickly establish a strong defense.
For instance, if Horde can move strongly enough to establish LM/BS/Farm very early in the game, then it doesn’t matter how many Death Knights are rolling around. If any of those are only barely held, or otherwise in a tenuous position, it becomes much, much more difficult to wrest back control of them.
Eye of the Storm is similar. Attempting to take three towers from the start has, so far, always ended in failure. Trying to take three at once (and the flag, too, sometimes) gives the enemy DK’s the perfect environment to simply drag fights out as long as possible.
They may not be consciously doing this, but that’s how the class seems to function in large scale PvP.
A heavy offensive in Eye results with little. Within a minute or two, players are spread out between three or four different points, embroiled in pointless fights with Death Knights, solidly holding nothing.
Sure, you currently own Mage Tower, but if even one more enemy shows up, it’ll be gone.
It’s a very fragile position. Basically, your side has overextended, and DeathKnights are the perfect class to capitalise on it.
After fighting off a few of them, the result is your team is, essentially, exhausted. Many cooldowns have been blown, your resources are slim, and even more Death Knights are riding in, ready to force you to use cooldowns you no longer have.