Infodump: Shiny, Albino and Melan odds

Here is a list of all the odds and modifiers applicable to Shiny, Albino and Melan hunting. First I must answer the question of why this information is "hidden". The reason for that is because it used to be public, the Shiny Hunting page would explicitly list your odds as "1/25" or whatever it was, and many users would complain that they hatched 26 eggs and got no shiny, failing to understand that odds don't mean guarantees. So, with the firm disclaimer that "1/X does NOT mean that you will hatch a S/A/M every X eggs exactly", here is the information. Shiny hunting: "Full odds" Shiny is 1/8192, as it was in earlier official games. The PokéRadar boosts this gradually until you reach a chain of 39 (40 with Hypermode), at which point your odds are 1/400 (1/200 with Hypermode). This means Hypermode is effectively a 2x modifier. The Gold Amulet is a 1.25x modifier. This brings your chained odds to 1/320 (1/160 with Hypermode) The Shiny Charm is a 2.5x modifier, active for 24 hours. Combined with the above, Charm-boosted odds are 1/128 (1/64 with Hypermode) The Pokémon of the Day is a 1.1x modifier, but obviously it's not something you can rely on for hunting, so won't be included in further calculations. Sei Power is calculated as SP = 50-(value shown), then takes your 1/X odds and returns 1/sqrt(X * SP). This is a more potent bonus when X is larger. - For full-odds shinies, Sei Power 5-25 yields between 13.5x and 18.1x modifiers! - Conversely, someone with the fully stacked modifiers of 1/64 would see Sei Power 5-25 yielding between 1.2x and 1.6x. Sei Power is meant to be a bit of an equaliser in that regard, though better starting odds will always yield better odds under Sei Power! All combined this means the absolute maximum odds you can have with all modifiers and 25 Sei Power is 1/40. Albino hunting: Starting odds are based on the Level that you charge the Albino Radar to: 1/[8192, 4096, 2048, 1024, 640, 360, 240] In March 2022 a global update was implemented applying a permanent 4/3x boost to all Albino rates, meaning the effective base rate is now: 1/[6144, 3072, 1536, 768, 480, 270, 180] The Silver Amulet is an additional 4/3x boost, resulting in: 1/[4608, 2304, 1152, 576, 360, 202.5, 135] A Z-Crystal matching the Type of the egg you are hatching (NOT taking Delta typing into account!) will provide a 1.5x boost: 1/[3072, 1536, 768, 384, 240, 135, 90] During the Type Race, an additional 1.2x modifier is applied to Eggs matching your Team (again, not taking Delta typing into account) 1/[2560, 1280, 640, 320, 200, 112.5, 75] This means that your best Albino odds will usually be 1/90, but can be 1/75 during the Type Race. Melanistic hunting: By default, Melanistic Pokémon are just Pokémon that happen to be Shiny and Albino at the same time. Since these are independent events, just take your Shiny and Albino odds and multiply them together. Assuming no premium items (Hypermode, Shiny Charm) or other temporary upgrades (Sei Power, Z-Crystal), your odds would be something like 1/(320 * 135) = 1/43200 -- a very rare occurrence indeed! However, with fully stacked items and on a max power Sei Day during a Type Race that matches your hunt, you can bring that number as low as 1/(40 * 75) = 1/3000 Two additional modifiers can impact this number: The Übercharm is a 6x modifier, lasting 28 days from activation, simple as that. The Cobalt Amulet allows Arceus-rank (or higher) users to accumulate a Long Chain Bonus. This bonus increases by 1.5% additively every 100 Eggs hatched, up to a maximum of 75% at 5k Eggs. Stack absolutely everything together, and the best possible Melanistic odds you can get should be 1/285... but it isn't. This is because of the implementation details: Melanistic modifiers work by testing to see if the Shiny check worked, and then conditionally modifying your Albino chances if so, and they are subject to rounding. Rounding is always done upwards, so even though fully stacking will yield a modified Albino chance of 1/7.14, that gets rounded up to 1/8 for a final Melanistic chance of 1/(40*8) = 1/320. Good luck!