Hello Team ESO,
Was trying to make a note within the game, but since the bug froze the game and kicked me out, it wouldn't have helped. If you think it would be better, I'll try to get near the spot where the latest instance happened and make the same bug report there.
I've had the exact same thing happen to me on three different occasions and it is very frustrating:
I'm in combat with a Troll Mage (in one case, in combat with two simultaneously) - each of these instances was in a different location. Though I had one location freeze and crash twice.
What: ESO crashes when combating Troll Mage (screen / game freezes forever then must be shut down)
Where: The fights have all been in Wrothgar.
Server: NA
Hardware: PC (Windows 10)
When: Already three separate times and counting
Who: I know you'll find this odd, but I can't remember if it was with only one of my characters or more. Character names: Farts-A-Bunch, Sweetpea the Destroyer (and Tamlorn The Kinda Skinny, but I don't think I've taken this character in to Wrothgar).
It *seems* to specifically happen when the Troll Mage does a down-sweeping gesture with its hand - as if they were tossing you coins awkwardly with their palm up and there is the snowflake "ching" sound. The image freezes, the sound freezes, the GAME freezes. I wait, and wait...and wait...and wait...and wait and good ol' Windows says "hey this app is not responding, whuddyah wanna do?" And if I just click continue to wait, then see previous part beginning with "I wait,". I finally have to have it shut the program down and relaunch.
I am currently doing a quest in the mountain in the middle of the map - Bonerock Cavern. But it has happened elsewhere in combat with the Troll Mages, just don't remember where.
It just really felt like there was too much competing data trying to come through the pipe and the game got e-constipation. My uninitiated armchair quarterback suggestion is to reduce the data throughput / output of that foe while in combat. Particularly it seems that the audio component is causing the trouble.
So, I hope this helps. Please let me know if I can do anything further.