Assuming they are all using their strongest team or what you could imagine being their strongest team.


This may sound like a bad answer but I am going to go with Blue. Mainly because he doesn't stick to 1 type like a standard gym leader. Just the ability to have a diverse team puts him a step over everyone else.

Whitney and her Miltank are obviously infamous, but I've personally never had a problem with her. Generally gym leaders in the vanilla version of Pokemon games are pretty easy, but I've struggled with Tate and Liza before. They use some decent double battle strategies, and they can be tricky if you're not prepared.

Just going to name some from every region.

Kanto - Brock if you're a charmander nerd who didn't know you could get Nidoran or Mankey. Ditto with Misty. Sabrina can get a little out of hand if you let her Calm Mind too much. The rest are very easy.

Johto - Bugsy in HG/SS, that Scyther is no joke. Whitney and her Miltank of course are dangerous as well. Clair's Kingdra is a demon as well.

Hoenn - Flannery's sun strats with that Overheat Attract Torkoal can be dangerous, I've seen numerous Marshtomps getting obliterated in that battle. Winona's Altaria is dangerous when you're not prepared, and Tate and Liza can destroy you in Emerald. Overall a very strong region!

Sinnoh - Fantina in Platinum is a demon, early Shadow Balls can wipe your whole team.

Unova - Unironically the first gym leader if you either don't know or don't care about the monkey. Elesa and Clay are also dangerous.

Kalos - All of these are very simple but I've personally struggled the most with Viola (yes the first bug gym leader...)

Galar & Paldea - Can't recall them ngl

I'll copy Ian and do one for each region cause that sounds more fun than spending an hour deciding who I think is the strongest lol.

Kanto - I'm going Sabrina I've played Gen 1 Kanto more than the remakes and she's a menace.

Johto - My pick is definitely Clair and her Kingdra totally not bias towards this one because of pixelmon.

Hoenn - I have to go with the only gym I lost when I attempted a nuzlocke in Hoenn so Tate and Liza are deceptively challenging.

Sinnoh - To be honest this is the first region I had to really stop and think about it I guess I'll go with Fantina though I don't recall ever really struggling with any of them.

Unova - I guess I'll go Elesa had to look at all the gym teams to make a choice for Unova.

Kalos - I recently had a playthrough I started where the Rock gym messed me up I really should learn Grant's name since he gave me trouble.

Galar - I'll go with Nessa during my nuzlocke I really struggled during her fight for whatever reason which is more than I remember about any of the others.

Paldea - I dunno but I guess I'll go with Iono who I have a vague recollection of having some issue with.