Initially made the thread for tips based on countering dungeons - but I feel like it does make sense to talk about affixes too.
Added your tip on Phantasm to the OP! Also adding Spiteful MC to that list.
Will probably try MC on the other new affixes this season too.
Fawther gave a lot of good advice above. Will eventually add it to the list as I go on, but I agree with almost everything he said (I don’t take PoM, but I can see the use for it!). Get treasures early if you can. This is ESPECIALLY good if you have a curse dispel in the group - they can dispel as people pick treasures up.
Pain supp (or even barrier) molten gold if needed.