I used a pretty nice strat to defeat Aderyine. You can transform his annoying misty field into a corrosive mist field by using smog, clear smog or poison gas. Afterwards I used gravity with clefairy to create a corrosive field (he can terminate the c. mist field with whimsicotts tailwind). Then I set up some cosmic power with clefairy and swept with it. I think you can change most of the fields to a corrosive field by using mist ---> smog ---> gravity.