The intent of the Heavy Ball, Leaden Ball, and Gigaton Ball seems to be that they have a higher catch rate than the basic balls in exchange for a much shorter throwing arc, rewarding you for sneaking up right next to a Pokémon.

But if you engage in battle first, there's no aiming involved and distance isn't a concern, you simply automatically hit the target. Do the balls' increased catch rates still apply in this case? If so, does it mean those balls are always the best option for catching alphas or if you fail to sneak up on an aggressive mon?

2 Answers

This part of your question is not fully accurate:

have a higher catch rate than the basic balls in exchange for a much shorter throwing arc

While Heavy Balls, Leaden Ball, and Gigaton Balls indeed cannot be thrown as far, this factor is not what provides the higher catch rate. These pokéballs provide a higher catch rate if the Pokémon has not noticed you.

[Heavy Balls] are thrown in a shorter arc and do not travel as far as the standard Poké Ball, but are highly effective when used to attempt a capture against a Pokémon that has not yet noticed the player.

_{Bulbapedia, emphasis my own}

and

Heavy Balls are a special variety of Poké Ball that are more effective at catching Pokémon that haven’t yet noticed you

_{legends.pokemon.com, emphasis my own}

So to answer your question, using heavy balls and its upgraded versions do not provide its additional catch rate while in battle.

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YES!!! They absolutely work in battle I have caught so many more alphas using the Leaden balls than great balls. Yes great balls work but not 100% usually if an alpha is being stubborn and is not being caught I will use a Leaden ball and it works first try. They definitely have an effect because the target is heavy. Feather and that class work on light Pokémon better. SO YES USE YOUR HEAVY TYPE BALLS ON ALPHAS.

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