Murkrow with Perish Song and a Focus Sash will take down a lot of stuff. Also, Sudowoodo with Sturdy and Counter one shotted Solaris's Garchomp at Pyrous Mountain for me.
Also, have you heard the legend of Scarborough?
It sounds like you played "Lin" route on the game. On the "Anna" route, Lin does not survive the events inside the Sanctum; you could say she died in combat. On that route, without much explanation, that she is a seriously misguided child who made companions with a god while trapped in a prison she had no business being in. Unfortunate, no child deserves that. It's traumatizing for any child, and then you throw a child that was already traumatized in the absolute worst way, and give them god like powers. No wonder puppet Lin was a blood thirsty psychopath. In real life, it would take decades of therapy (not from Dr Sigmund) for Lin to fully recover from something like that.
Honestly, from a role play perspective, the Anny route was the only route for me to take.
After playing the Anna route, I went and started Pokemon Arceus and named the main character Lin. Because, why not, it fits in a really weird way. At least in my mind.