Blackjaw type commander in temple, damage seems wrong

177475192 bug report reference number

I've died a few times to this enemy in the temple during campaign (usually around act 4/interludes) in ways that don't seem to make sense.

First time was a character with 85% all res (was using saffels + anvil), 1.3k life , and 65% phys taken as ele (cloak of flame + shaman, and the rest of the adaptation nodes from shaman) and got full to 0d in one hit. I was in the 2nd interlude at the time, around level 60.

I went back and ran another temple as soon as I could and stood face tanking the same enemy type for a while and couldn't ever get hit for more than 15%ish of my health. Here's me tanking the cleave on the same character for example:

https://imgur.com/e2fUoDp

Second time full to 0'd by the same enemy type in the temple just now on a level 54 with 75 fire/49 cold/ 69 lightning res from far away. I am not sure what hit me in this scenario even, it seemed like a tiny rock flew and hit me for my entire health bar.

Could definitely be wrong, but something seems off about the amount of damage this enemy does in particular.