Death through shields.

ACT 3
Level 42
SSF Hardcore.
Character if needed Name HudsonHughes

Insta death. Ignored shield and was using Grim Feast (Buff) fully charged.

Ablation (Support) sometimes takes more than 15% life.
Might be if minions die/if you click more than once/minion out of range? No idea
(Might be related, don't know)

Death Picture
https://imgur.com/a/aSsfjyY

GGG Joke
https://imgur.com/IMopZJI