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What do you mean for eviolite Magneton having "More space for power"? Other than that, I can see that this team definitely works pretty well. One more thing: LOLSTUNFISK.
I think it could hold a nice role as a trapper. Switch in on something that fears Head Charge and predict a switch. I might have to try that out sometime.
I actually ran a weather ball set with Roserade last gen, it worked pretty well. I can only remember the actual moveset.
Sunny Day
Rain Dance
Solarbeam
Weather Ball