PSA: Regular (non-Beast) balls have a 0.1x ball bonus against Ultra Beasts

antialiasis:

Or, at least, it definitely looks like it.

The common wisdom, on Bulbapedia and every other online discussion I could find, appears to be that while Beast Balls have a 0.1x ball bonus against non-Ultra Beasts, other Pokéballs (except Master Balls) all have a 1x ball bonus against Ultra Beasts. However, the other day, someone e-mailed me saying they’d had a far more difficult time with Nihilego than my calculator suggested, and as a result I took a look at the S/M capture routine again and realized that there’s a part of it that’s overwriting the ball bonus value with 0.1 if the item ID is not 851 and [some mystery condition calculated based on the Pokémon]. Item 851 is the Beast Ball. In other words, some condition involving when you’re not using a Beast Ball also sets the ball bonus to 0.1.

Obviously, the natural conclusion would be that the mystery condition is checking if the Pokémon is an Ultra Beast – what else would be dependent on whether you’re using a Beast Ball? Plus, it just makes sense – it’s nicely symmetrical with Beast Balls against non-Beasts, and the in-game dialogue makes it sound like normal Pokéballs work poorly against Ultra Beasts, not just that they don’t get their special bonuses. And conveniently, I hadn’t actually caught all the Ultra Beasts on Sun, so I could attempt to verify this myself. See the readmore for the statistics, but basically, I’ve established pretty confidently that the bonus being 1x does not make sense, whereas 0.1x is reasonably consistent with the data.

Thus, I’m updating my calculator and capture mechanics page to reflect the conclusion that the ball bonus is set to 0.1x for Ultra Beasts when the ball is not a Beast Ball. Since this simply overrides the ball bonus after it’s calculated normally, there is no difference between different balls, and balls that give bonuses under certain conditions will never give them against Ultra Beasts. (Note that Master Balls will still always succeed, however.) Pass it along!

Keep reading