so the other day men and my lvl 14 duo killed grog the troll (lvl 18) in 1 turn. (lonewolf tactician)
Start by taking you´r polymorpher down to 1 health with the help of living on the edge and initiate the fight, take down he´s physical armor and have the polymorpher use forced exchange and finnish him off.
This is a very broken skill that needs to be fixed, with it you can kill any mob as long as you mange to take down he´s physical armor
The developers have said this is intentional, and that they aren't going to remove these types of combinations from the game. If you figure out a killer combo and want to keep using it throughout the game, then go ahead. If you don't want to, then don't use that combination. http://www.pcgamer.com/an-infinite-damage-combo-has-been-discovered-in-divinity-original-sin-2/
For now, rather than 'fix' the combo, Walgrave says they "applaud" it. Examples of techniques that would be patched out include anything that "breaks the fun" or is actually a bug. "If this would tick in realtime, it would be a bug," wrote Walgrave. "And if this does not cost AP/skills and/or is not blocked by cooldown/consuming a scroll/... then we look into it."
It's not broken, it's a technique that you can use. Skill points are consumed, APs are used, you must set it up beforehand and choose to do it.