[OVERVIEW]
-Magikarp is known as the worthless, pathetic, weak, and the punching bag of the pokemon world. Well that is true.
-He has 80 base speed which is a true gift in NFE, however he also has 10 base attack and decent defense, but disgusting special defense.
-Not all hope is lost for this mighty fish, if he has baton pass support and entry hazard support, the punching bag of the pokemon world can redeem himself.
-With is Hidden Ability Rattled, Magikarp gains speed to Dark, Bug, and Ghost types, being able to switch in on them for speed. This makes him a bit better than his brother Feebas (not really).
-But, he has a VERY shallow movepool which is one of Magikarp's many drawbacks.

[SET]
Set Name: Rattled
Move 1: Splash
Move 2: Tackle
Move 3: Flail
Move 4: Bounce
Item: Eviolite
Ability: Rattled
EVs: 252 Atk / 76 HP / 180 Spe
Nature: Adamant

Set Comments:
-This is his best set (surprisingly -,-).
-Bounce is his most powerful move, but he can be easily killed by Thunder.
-Bounce also is good against Bug types which he gets speed from.
-Flail is also a good option if Magikarp is low on HP.

Additional Comments:
-Splash does nothing so get used to it.
-Tackle is just a filler move since, Magikarp only has 4.

Teammates and Counters:
-Baton Pass is required from Scyther or other Swords Dancers for Magikarp to reach it's full potential. If you can pull it off, with +4 Atk and a sub, my hat goes off to you.
-While in sub and Magikarp gets hit by a Dark, Buf, or Ghost type move, Magikarp gains speed and is ready to sweep.
-Entry Hazard support is loved by Magikarp, making his job easier.
-ANYTHING can counter this fish.

[SET]
Set Name: Swift Swim
Move 1: Tackle
Move 2: Splash
Move 3: Bounce
Move 4: Flail
Item: Eviolite
Ability: Swift Swim
EVs: 252 Atk / 76 HP / 180 Spe
Nature: Adamant

Set Comments:
-Now Magikarp as a rattler is the better option, but Magikarp in some rain, can outspeed many in the NFE metagame.
-The moves are basically the same as the other set, same purpose.

Additional Comments:
-Rain tends to run out when Magikarp gets his pass.
-Magikarp rarely sweeps in rain, but you would need a Swords/Rain/Sub/Baton Passer in order to give Magikarp some power.

Teammates and Counters:
-Magikarp needs more support in this set, making it harder to sweep.
-Again, many can counter this scaly fish.

[TEAM OPTIONS]
-Magikarp is outclassed but the other Rattlers Ledyba, Snubbull, Poocheyena, Bonsly, Clampearl, and Cubchoo.
-If you dare use Magikarp then you better have the following:
-A Rapid Spinner
-Entry Hazards
-A Swords Dance and Sub Passer
-Rain Dancer (Swift Swim)

[OPTIONAL CHANGES]
-You can have Max Speed EVs for the Swift Swim set, but that is just foolish.
-Other than that, you are limited to these sets.