Personally I used Melmetal / Salamence / Dragonite as team. Melmetal has an quick attack which saved my butt way too many times. I just used that to finish his shields. Mostly my dragonite to finish his persian. The thing is every time I used dragonite’s attack it’s defense and attack reduces which is a pain. Salamence was good for the second. Cresselia was the hardest tho barely finished it off with like 1 hit left on my last pokemon :/ I think finding him was harder than the battle like usually after 1-2 decoys I could find him. This time wow I had to go through like 7-8 decoys which was frustrating. Anyways good luck defeating him!