01/30/21: Gen II catch mechanics updates

I've updated the Gen II Capture Mechanics and Gen II Catch Rate Calculator to incorporate a couple of additional (relatively) newly-discovered quirks in Gen II's capture routine:

  • Kadabra, Tauros and Sunflora all incorrectly get a Heavy Ball bonus of +40 in Crystal (but not in G/S), because the game fetches their weights from the wrong ROM bank and ends up with junk data that it interprets as a massive weight.
  • Level Balls skip the entire HP and status part of the calculation and make the final capture rate just the intrinsic capture rate with the appropriate level multiplier. This means that Level Balls are actually one of the best balls in the game even if your Pokémon isn't higher-leveled than the opponent - effectively they always act as if you've lowered the Pokémon down to zero HP. While all other balls cap out at a 1/3 chance of catching a Pokémon at full health, Level Balls are guaranteed to catch a 255-catch-rate Pokémon at full health - again, even if your Pokémon is lower-leveled. This is not a glitch - by all appearances it's intended behaviour! The game specifically checks if you're using a Level Ball and then if so skips most of the calculation. (However, this is not the case in HG/SS.)

The Level Ball thing kind of just blew my mind. Please do play around with the updated Gen II calculator.

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My own messages will be signed as Butterfree, with the Admin label below my name. If someone signs as Butterfree without that label, it's probably not me.

Commenting on: 01-30-21

The calculator spouts some weird NaN stuff if you use the new Level Ball formula stuff and get a guaranteed capture.

[10/02/2021 11:18:16]

Commenting on: 01-30-21

That's really interesting. I believe that it fits in canonically with one of the "Pokémon Adventures" manga scenes in which Crystal throws a Level Ball at full-health Arceus. However, that was in the HGSS arc, so I'm not sure whether it was informed or just by chance.

[01/02/2021 14:59:15]

Commenting on: 01-30-21

Oh, how interesting about the level ball!! How does it work in later gens like HGSS?

[01/02/2021 07:29:40]

Page last modified November 2 2020 at 21:21 GMT