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Got a problem with the damage calculator as well, as you can see in the screenshots when Psycho Boost is selected to hit twice, the amount of damage goes through the roof. It is not the system not taking the -2 from the first attack into account, but it is also getting extra damage on top.
More or less looking for some clarification here, why is Mega Swampert not ranked? It gets rain and +2 speed first turn, and then in that same turn it can smash something with a rain boosted stab Waterfall. I really don't understand why it is not up there with some of the mons that are.