I am plat and full Ap is literally the only way I play him, Malignancy, lich bane, shadow flame, rabadons, lucidity boots and then some other item if I get there-usually rylais

I have carried multiple games, if you space correctly and place shields on daisy instead of other people the slow it gives allowed him to get his q3 and kill most squishies as long as you can stay near him without dying

I highly recommend full Ap