This happens to me aswell. I think its because of ronda blocking the didn't need 'em passive resulting in a 40% health reduction. That makes his health negative meaning he cant die

All indications I've had have pointed to this being a visual bug (with UDK still getting life back from gear, but the life bar being bugged)

But, will look into this.

So let me preface this by saying I have some background in game design and beta-testing, so this is educated speculation 

This is "a thing" but I'm not seeing YouTube content creators making videos about it and usually we'd see that, especially with all the comments on Reddit and other sites. Some of the posters are hitting UDK with what *should* have amounted to WELL OVER what is possible for any kind of gear or buff could have saved him. I came looking because I thought it was some new kind of "unkillable" thing people had figured out and as a F2P player, I really needed to compete with it. I've seen tons of speculation about left over buffs from dead alies, stoneskin, this visual glitch and others. 

Whatever it is, some people seem to have figured it out, because there are *specific* teams (which I will document from here out) in the arena that UDK won't die, yet fighting other teams with UDK, beating them is as normal. I feel like there's something very specific going on here as a mechanic, whether it's something with a buff from a dead alli, a gear set, or some other attribute. But the fact SOME people have the information and the majority DON'T, this gives a small percentage of players what amounts to an unfair advantage and Platinum should step in and either fix it or publicize the solution to everyone. 

I originally thought it is a visual bug caused by his Didn't Need 'Em passive, but it would mean that it only happens when his allies are dead (cause that's when he gets extra HP). Today I realized that it is not the case. I could not kill him while all of his allies were alive so it has to be something else.

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He could absorb tens of thousands of damage with no HP left on the bar and still not die.

. My friend get the same problem about Unkillable UD. He use Android phone.

. From my own experience: I have met a few times that UD won't die, but it just happened 1-2 times per battle, and happened 1/10 battles. I play Raid on PC.

. Hope to have an answer from support team, even just to confirm "yes, that's a bug, will be fix...". ^.^

I get this same problem as well.  No matter how much damage I did and even if Ronda disabled skills, UDK would not die.  It happens fairly often.  I've let it auto run and hit the round cap as well.

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Edit: Actually fought this team a 3rd time and it killed him.  I wasn't keeping track of the rounds, but it was way less than when the round count pops up.  lol it straightened up after I "told on it". :p

Here is a total fail run:

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Healing 11K at turn with empty HP bar it's insane... 

I got stuck multiple times lately... 

The HP bar is bugged af

This is 100% still happening, with Ronda in team. She often has been the 1 thing that allows me as a relatively new player to actually take down the #1 most annoying thing in arena so far, UDK. I could beat *5 UDKs with enough aoe damage but *6 ones literally took Ronda to turn off the effect. And then this thing happens. I had him down to no health in about 7 turns but then fought him for another 10 minutes, with him on empty before he died. I was beating on him with my 60 Kael, 60 Ronda, 50 Pythion, and 50 Magnarr. He ended up taking way more damage than his heal number. And that is considering all the single hits that never land because of his mechanic. Even with Ronda blocking his active and passive effects, he would take very low damage with kinda a light blue color numbers.

Since this has been reported, any idea on when this is getting fixed?  I am currently in an arena battle where i have "killed" him 5-6 times already, but he doesnt keep dying...he keeps healing up from zero health even though i have blocked his abilities with Ronda - its been around 40 minutes now.  When on zero health, i can see the yellow numbers of the damage 

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Approaching turn limit...and i've probably "killed" him now more than 10 times

I have seen the no death but, I also see him simply out heal all damage. My team might have a 20k -30k power advantage, his entire team is easily killed, and he will not die. His passive heals outheal the damage of 3 attack champs attacking for mutiple rounds and he can even slowly bring their health down with his single attack skill. Healer heals, and you are just topping him off at max health. 

I have been a gamer for 30 plus years and I have never seen anything so incredibly dumb besides people outright cheating. There are multiple bugs with this champ and surprise, he is probably the most used in PVP  
:(

Same thing happened to me today, spent more than 15 minutes and gave up.

i

Seems like this is still an issue that has not been resolved.  I just experienced this gain now - took an additional 2-5 minutes and he eventually died.  Killed him so many times before that...and he just was not dieing...again.  Is this ever going to get fixed?

I've had to forfeit 2 arena games in the last 2 days where it took a while to get him down to an empty bar but then he just wouldn't die even after spending absurd amounts of time trying and the bar not . Brimstone procs don't kill him, nothing does. The guy is a big enough nuissance in the arena to begin with, but this is the icing on the cake of annoying where you spend longer to get him down than the rest of his team, and then he does this. I've seen this happen on UDKs that took damage moderately easily, and also on ones that were highly resilient both. I've not seen it happen on a 5* one. They just die.

Still a problem.

So, end the fight or wait an hour and a half just to loose anyway.....solution don't fight a team with deathknight!!!! So stupid to spend money for this bull. 

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