Hardest: probably the first 2 gyms, Venam and first fight vs Keta. It might be weird but I consider those to be the hardest gyms simply because u have the least amount of options available to you in terms of pokemon at that point in the game. Although this could've been influenced by the fact i did my 1st (and only) run on rejuvenation on intense mode only, I still believe even if I had prior knowledge of both gyms, they still would be hard.
Reasons:
Venam:
- Her field significantly buffs her own side, through activating venoshock, she literally has access to a 130 bst move that early in the game, while most of your moves would be around either 40 to 60 bst, there is simply no comparison.
- Her mons are simply naturally tanky as fuck. This is compounded by the fact that ur moves are weak in power at that point in the game, and that poison is a good defensive typing with two weaknesses.
- Again, due to limited options available at the beginning of the game, u can't effective target her pokemon's weakness or change the field. Purify is the only move that changes her field and u don't get access to any pokemon to that until terajuma (pyukumuku). You literally have ZERO strong ground type attack options at that point in the game unless u chose mudkip as your starter (and even that is a moot point since mud shot gains poison typing in the field, nullifying its super effectivenesss). There is no ground type u can catch at that point in the game other than geodude and nidorans, and those don't learn any ground moves at that level in the game. There is also no pokemon that u can catch that can learn a strong ground type coverage move. Having a chingling or woobat is basicallly mandatory for this gym, but those can't get past the brick wall that is alolan-grimer due to its dark typing, and both being frail and lacking a resistance to poison make it hard for them to last in the match
- Alolan-grimer might as well have no weakness in that match, due to the aforementioned points and dark-typing, its extremely difficult to take down without losing one of ur own pokemon unless u already have a pokemon on the field that has setup multiple attack boosts (pokemon that can set up and sweeper are limited too at this point in the game). At least it doesn't hit too hard, but due to its bulk it probably ends up doing to most damage to your team getting off severals hit and poisons status.
- Overall the fight is hard primarily due to the limited options you have, combined with the fact that her team simply overall outguns and outlasts. Unless u have like 2-3 woobats/chinglings + something that can beat alolan-grimer in a 1v1, any other possible teamcomp at that point in the game will find this a great challenge.
- Again, maybe its a me problem since I dove into this without having any awareness of the true difficulty of the game.
Keta 1st battle:
- This. His pokemon completely outstates your pokemon. He has a fully evolved team already bar pignite. Like seriously? This time, unlike venam team, his team basically outguns, outlasts, and ALSO outspeeds you. This is basically the primary reason why this fight is just so hard. Each single one of his pokemon just has much better stats than your own and anything u can muster at that point in the game.
- The doubles format accentuates his stat advantage and offensive pressure
- His pokemon pack strong moves like rock slide, strong priority moves, gale strike, etc. Ok granted maybe those aren't that strong on an absolute scale, but those moves are too good at that level and stage of the game.
- Breloom packs spore when u are able to live an attack. At least that one of the few things u can one-shot potentially with a fire move.
- Several of his pokemon hold a seed that granted it a spiky shield when they switch in, giving that mon a free turn to fire off a powerful attack without retaliation or even set up.
+ At least the highest possible bst mon u can get at that point is i think is lunatone, with bst of 460, which can pack a strong psyshock for that fight if u go to the move tutor, and can live one gale strike (due to field its super effective)
+ The doubles format actually can work to ur advantage if u abuse the AI. Usually i found that the AI always tries to double target the weaker mon on your side, especially if said mon has a great weakness and can be one-shotted by either of the opposing two mons. Thus I cheesed this battle by using lunatone+a mon that baits AI double targetting, with combusken killing breloom, swoobat doing a bit of damage, and lunatone killing everything else.
As for the easiest its honestly probably any single battle gym leader including and after Amber. By that point in the game you have access to enough options to feasibly just wall out the opposition with some tanky pokemon (blissey, amoonguss, toxapex from mystery egg, avalugg).