Ludicolo with Rain Dish
Vaporeon, lapras, and Dracovish Give them all water absorb Give Dracovish the choice item that increases speed and have it ONLY use Fishious rend Gove Vaporen and Lapras Surf, and muddy water and rain dance if you don't already have that this is especially helpful in double battles
I'd say just diversify as much as possible with each Pokemon preferably having two typings that no other Pokemon on the team has personally I usually have an alolan Ninetails and a gmax Toxtricity
A ludicolo both abilities help it very much or something that could abuse thunder
I agree with sir shinesalot
Dracovish is a formidable option on any rain team as it’s signature attack Fishous Rend is able to reach base powers well beyond what is “natural.” Adding the rain on top of its already overwhelming power will allow you to defeat even the bulkiest of foes.
Pikachu with surf and thunder!
An Inteleon is a good rain Pokemon.
Anything that improves it😱