I want to get better at Pokemon battling in Violet…

Competitive in SV has become easier than ever before. You could reset a Pokémon's EVs using stat-lowering berries or reset Mochi,

and then upgrade the Pokémon's best stats using stat-boosting items like HP-ups or defeating a ton of Pokémon that give you specific EVs (example: Houndour gives Sp. Atk EVs, and Chansey gives HP EVs), preferably while holding one of those items that give you more EVs for a specific stat after a battle but lower your speed (I forgot what they were called because I'm rich and just buy stat-boosting items).

Use mints to further boost the Pokémon's stats, giving it a nature that lowers its worst/least necessary stat (example: a Meowscarada with boosted attack or speed and lowered Sp. Atk).

Use Bottle caps and Gold Bottle caps to maximise a Pokémon's IVs. Some strategies involve giving a Pokémon zero or low IVs in one stat or more.

Take Type Matchups, STAB (Same Type Attack Bonus, where a Pokémon using a move the same type as it is makes the move stronger), stats, Type Coverage, common opponents, and the rest of your team into account when deciding moves. You don't want to have zero good moves when a Pokémon or Terastallized Pokémon with a type you don't expect comes into the battle. And you probably don't want to use a move like Earthquake if you're doing a Double Battle and one of your Pokémon has a 4x weakness to it.

Use Pokémon with great type combos and amazing stats and abilities, and wide movepools.

Those are the basics. There's a lot more complicated stuff if you want to be a professional at competitive, but I am not a professional and can't provide the information required to be one.

Another tip is to consider the team you’re building, if you have slow Pokémon, I recommend Trick Room with low Speed IVs, for Special Attackers, low Atk IVs (Confusion and Foul Play deal damage based on the target’s Atk stat. Use Mints to get the natures you want (Adamant or Jolly for physical attackers and Modest or Timid for Special attackers)

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