How do I beat this?

Don't leave your Steel or Grass answer in front of it in the sun — a sun-boosted Fire move that would be a safe switch under neutral weather can outright OHKO.

Don't let it get the free Unburden turn.

Don't Fake Out the Farigiraf to stop the Trick Room — Armor Tail makes it immune to priority, so your Fake Out whiffs and you lose the turn.

Don't chip it with weak physical contact — every hit it survives raises Defense via Stamina, so you're feeding the exact stat that makes it unbreakable.

Don't try to out-click it in the rain with a slower attacker — Swift Swim means it moves first and the rain-boosted Water hurts more than you expect.

Don't lead your Intimidate-weak physical attacker into it expecting to trade — the -1 from Intimidate plus a Band Brave Bird usually means you take the hit and hand it free momentum.

Don't Taunt the Hatterene setter — Magic Bounce reflects it straight back and now YOUR mon is Taunted.