I managed to do it with Altan in Lifesteal and Tyrant Ixlimor in... something tanky.
Anything that has a good unkillable will work too like Paragon and whoever else you want.
Without some form of unkillable or damage negation it's entirely RNG based.
It took me 16 runs to get the boss to proc on Altan while ally protect was still on him.