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can be dismanteled by strong wallbreakers such as Garchomp with an boosted Earthquake or Fire-coverage in Fire Blast, which helps Garchomp going through Ferrothorn.Gen8 OU question: What's some ways to counter rain in a balanced team? Specifically I'm having trouble dealing with Ferrothorn and Barraskewda
Rillaboom and Kartana are both immune to its Leech Seed and Kartana wont take a lot from Stealth Rocks due to its part Steel-typing. It can dish out a strong Sacred Sword on it. Same goes for Rillaboom with Superpower, however both have to look out for Knock Off and Thunder Wave as it cripples them severly.
Tornadus-T and Zapdos are also great against Ferrothorn in rain-teams as Tornadus-T threatens it with a Focus Blast or Heat Wave, and outside of rain Heat Wave will do a chunk, Zapdos doesnt have to fear Thunder Wave and can cripple Ferrothorn severly with Heat Wave and Zapdos can effectively Defog on it.
Can be answered with Slowbro and Tangrowth as both dont have to fear much from it, however Slowbro has to watch out for Crunch coming at its way, but Tangrowth is 1 of the best answers against Barraskewda.
Rillaboom can help versus rain, as its strong Grassy Surge-boosted Grassy Glide picks of most Teammembers of from rain teams, that counts fro Crawdaunt, Barraskewda, and Urshifu-R.
Other strong tanks such as Toxapex can help versus Barraskewda and also Urshifu-R, furthermore Toxapex can help with dishing out Toxic or Toxic Spikes against them to disrupt their effectiveness in the long term. Toxapex can also use Haze as an option to help versus Setup Sweepers in Rain teams.
Tapu Fini is also a great answer versus the above mentioned Rain-abusers as it wont take much damage from all of their attacks they go for and has Leftovers and can also use Draining Kiss for some recovery during the process.
Hope that helped :)