Larian Studios Forums Divinity: Original Sin 2 Divinity - Original Sin 2 - Suggestions and Feedback [Bug] Bridge Trolls can't be defeated.

They're immune to decay
They're immune to knock up and teleport

They have no magic resist
They have weakness toward a certain element
They can be Stunned/Frozen/Chicken chained

Also

Troll blood can be disabled.

Killed the level 15 one at level 13 and I'm about to go after the other one.

And you're not supposed to go after them at level 10. The golden rule of Divinity is to avoid fighting anything 2 levels higher than you and that weapon should never be 2 levels below you or lower.