Most of them are plain killing, cunning you first have to heal to beat the other guy (healdrops from surrounding mobs) Another one has mobs around you have to kill to break his shield, another one pops a shield and you have to use the objects around him (the one that lights up, repeat till his shield breaks).
Another one would be darkness and you have an item in your bag to make him appear if too slow at killing him.
And I think the only maybe tricky one left is the trio that heals each other except for when in the circles that spawn on the ground.
Honestly though, I found these to be very easy to figure out, these mechanics seem rather intuitive AND the mobs die easy
