Here is a recipe for 6s 205 All-ATK. This is 100% in the last step and does not require boost week, but it would cost an insane amount of meseta to setup, probably on the order of billions.
You can get 210-ATK by substituting Ether Factor for Doom Break II. You lose the 100% guarantee in the final step, though. This recipe is only for the criminally insane.
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