Kithros

I don't think any noteable trainer that we never fought is going to die, at least until we get the chance to fight them once. It's kind of metagamey logic but I seriously doubt they would show off Amaria's level 70+ pokemon while we had a level cap of around 35-40 if we never saw them again later in the game. Also, WHAT THE FUCK IS A PHYSICS?!!!

I had a Greninja that could outspeed and OHKO all of her pokemon except for garchomp and quagsire (and quagsire could get 2HKOed by extrasensory with the psychic damage buff from the field), so the fight was really just all of my pokemon other than greninja vs. her garchomp - and while the garchomp is strong, it's not going to be sweeping my entire team single handedly. If you're not using *any* water pokemon I guess that's a problem - I've practically never played through pokemon without using a water pokemon of some kind though (especially since having no water pokemon makes surfing a nuisance, when surf is one of the few actually good HM moves).

Julia was definitely the easiest - on my first attempt I just swept her with a loudred doing nothing other than spamming echoing voice. Samson and Terra were also really easy - Terra's Garchomp was a bit threatening, but my Greninja could just sweep everything other than the Garchomp reall easily so I only needed to be able to beat the garchomp with the rest of my 5 pokemon to be able to win. Samson didn't seem like he had anything threatening to me except for his last pokemon with the kind of cheesy fly mechanics on that fight (until it got paralyzed at which point it was just like any other pokemon).