Copy-paste much? xD
"Magikarp is an excellent sweeper, under Focus Sash and Flail-ing. If you're hardcore, you may also want to use Flail or Bounce under a Choice Band. Preferably, all of this under rain, to boost its Speed to higher levels. I believe a Jolly Magikarp with 252 EV's in Speed (and in rain) boosts it to 568, which for Magikarp is not bad at all. Alternatively, a better set would use the Adamant nature, which increases the Attack, and in the desired conditions would still reach a Speed of 514. If you Rain Dance, SubDrum, and then Baton Pass with a Poliwag/Poliwhirl/Poliwrath (unsure if Politoed does it), you can destroy worlds with Magikarp. An Adamant Magikarp with 252 EV's in Attack and Speed with 31 IV's for each plus in rain with 1 HP using Flail under a Choice Band would be the preferable set. Against a Shuckle, widely renowned for its extremely high base Defense, it is guaranteed a 2HKO if the Shuckle in question has 252 EV's in Defense, max IV's, an Impish nature or similar, and has no Defense boosts.
Simply put, Magikarp is f**king amazing."
I wrote that a while ago. I think it still applies.