In The arena I have been noticing that ultimate death knight getting an extra 15% heal when his continous heal buff is active and then still getting it after the buff has worn off. It doesn't happen with every udk but on my level 34 account it makes is pretty much unkillable. I though it could be from armor but to my knowledge there is no armor combo to give a champ 15% combined heal. the heal amounts are the same amount so I know it's the same percent of a heal. Also he will visible drop to zero and continue to heal through the passive skill and also through abilities and the heath bar will not show an increase or decrease in hp. I have inflicted 30,000 over 6 turuns to an udk that appeared to be at zero hp and it would not die. 

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