Lightning strikes bosses

Not sure if anyone has posted this yet but I just discovered that lighting can strike bosses and it does a lot of damage to them!

Decided to give expert skeleton a go without any set up, had decentish gear for that stage of the game but wasn’t really expecting to win. However lighting struck one of its hands at half HP and instantly killed it, from there I realised if you just keep dragging him near trees that are flagged for lighting, the flag transfers to him and he gets struck for a lot of damage! Made him very easy to cheese!