I agree with ji412jo. 4-5 rainbows that can be swapped around slightly depending on who plays against whom. If water does not have much CC, we pack in the creatures there, where as aether has more permanents, we pull the deflags there. It will still take some lucky guesses, but the more 'pot' ready for rainbows, the more we can 'stir' it to create a solid deck for each appropriate fight.