I play Feral Druid in PvP a lot and one thing I noticed Death Knights are lacking is an ability that makes me and other melees want to switch off a Death Knight. Warriors for example have Shield Wall, Ferals have Survival Instincts and sometimes Dispersion and Divine Shield, Rets have Divine Shield and HoP, Mages have Ice Block, the list goes on. Almost every single class in the game for the exception of maybe Shamans and Boomkins have something to make melee attackers want to switch off to a different target.
So, here goes.
Embrace of Death
Whenever you fall below 35% health, you prepare yourself to join death once more. For the next 15 seconds, direct physical damage will cause you to gain Numbness. Effect ends if 5 seconds elapse without any incoming physical damage. This ability cannot trigger more than once per 60 seconds.
Reduces damage taken by 5%, stacking up to 5 times. Upon reaching a fifth application you become one with death, granting you immunity to all effects which cause loss of control for 10 seconds and allowing the use of Death Coil on yourself.
This alone is probably not enough to save Death Knights still, but paired with Icebound Fortitude, it will surely make melee want to put pressure somewhere else.
Obviously all the numbers, such are duration times and damage reduction percentages, are on there just so you get an idea. If you think it's too overpowered or underpowered then suggest ways of tweaking it. Anyway, there it is, am ready for the incoming flame xD.