Hi again, thanks to all who have helped thus far!
By way of update, I got past Harmony, Audrey (she was a joke, easy to Sub on her Lanturn and boost), Anastasia, Taen v2 (such a funny battle- critted his Mega and A. Zekrom to death, got froze by the Kyurem, defrosted immediately after and KO’d it), the crazy old lady in Oranos Town (caught the Gengar on the switch with Crunch so it didn’t Mega and make my life miserable), Zenith v1 (honestly one of the easier matchups so far) and Taen v3 (super frustrating when your teammate spams useless moves as they’re being massacred by a Mega Typlosion and two Ubers, but finally managed somehow).
Now… I’m at Calreath. Full rain team, permarain with three setters even if Kanga could learn Sunny Day (which I’m pretty sure it can’t). As of yet, I haven’t made it past the D. Dragonite (Swift Swim, Choice Band, rain-boosted and STAB Waterfall…uugghhh). So! I again ask you, my fellow trainers, do you see a possible solution to this predicament? I’m at the level cap (79), with Cal’s highest being 75. Advice/comments is/are always welcome. Thanks for reading!