>>58906266Really depends.
XY has some nasty fucks, there's also Milotic encounter in RS post-Fortree that can be tricky due to rain and overall bulk - hilariously it was replaced with Thunder and Weather ball that also can be quite scary if you underestimate it.
Also - in Scarlet and Violet you can visit route leading to E4 very early in the game - you can grab there some nice encounters, few Gimmighoul coins and a TM... and there's the Black-bordered trainer with team in I believe late 50s or 60s? If you foolishly decide to fight it without previous knowledge about it, you may get obliterated immediately.
Also, I vividly remember in Platinum a Raichu/Gyarados double battle in the foggy weather. Both cover eath other's weaknesses pretty well, can hit very hard and are annoying due to fog.
Also, more of a mid-boss counters but rivals in BW have tendency to jump at you at the end of the route with no warning. They are not difficult but you can be simply unprepared to fight them because what kind of retard will be going back to the previous city just because there's a chance that Bianca will jump at you from behind with her starter and a patrat?
