SwSh RNG

[burb00]

Just a quick question. Does Pokemon SwSh uses RNG correlation or csprng on eggs and fossils restored?

[SkyLink98]

Eggs have a 64 bit Xoroshiro seed from which stats are calculated. The seed is cryptosecure generated, so can not be manipulated.

Fossils should be standard static encounters, so cryptosecure unless you patch the game to use the global Xoroshiro state.

[burb00]

Thanks for the answers but I am still a bit confused. So, here are a few more questions hope you don’t mind:

1.) If the encounter type uses cryptographically-secure RNG, it will be impossible to manipulate and therefore all legal combinations of stats will be possible on a pokemon?

2.) If I shinify an egg obtained from the daycare in SwSh. Does the PID still matches the egg that was shinify? Since eggs uses cryptographically-secure RNG where all results are possible?

3.) Pokemon in SwSh that uses cryptographically-secure RNG are:

- Scripted static encounters such as regis (including regigigas), Zacian/Zamazenta, Eternatus?

- Gifts pokemon such as fossils, Kubfu, Type: Null and Cosmog?

- Eggs from Daycare?

4.) https://x.com/SciresM/status/1319878015581523968

From the link above, it says that max lair pokemon uses cryptographically-secure RNG. However, if not mistaken changing any values for pokemon caught in max lair will result in an illegal pokemon. So, which part of the sentence is right?

[SkyLink98]

1 hour ago, burb00 said:

1.) If the encounter type uses cryptographically-secure RNG, it will be impossible to manipulate and therefore all legal combinations of stats will be possible on a pokemon?

If the encounter uses cryptoscure RNG to generate all the Pokémon properties, then yes.

1 hour ago, burb00 said:

2.) If I shinify an egg obtained from the daycare in SwSh. Does the PID still matches the egg that was shinify? Since eggs uses cryptographically-secure RNG where all results are possible?

Eggs use Xoroshiro, so technically, calculators that brute-force the seed can be built. That said, the 64bit seeds should provide enough space to allow for all possible PID-IV combinations.

1 hour ago, burb00 said:

3.) Pokemon in SwSh that uses cryptographically-secure RNG are:

Static encounters (which includes gift mons). Wild encounters are generated through the global Xoroshiro states, while Eggs, Dynamax Raids and Dynamax Adventures have their own Xoroshiro seeds.

1 hour ago, burb00 said:

4.) https://x.com/SciresM/status/1319878015581523968

From the link above, it says that max lair pokemon uses cryptographically-secure RNG. However, if not mistaken changing any values for pokemon caught in max lair will result in an illegal pokemon. So, which part of the sentence is right?

In the case of Dynamax Adventures encounters, cryptosecure RNG handles the shinyness. All the other pokemon properties are Xoroshiro. If the cryptosecure RNG decides a Pokémon has to be shiny, the PID gets modified to be shiny, becoming uncorrelated from the Xoroshiro seed.

[burb00]

On 4/26/2025 at 6:03 AM, SkyLink98 said:

If the encounter uses cryptoscure RNG to generate all the Pokémon properties, then yes.

 

Pokemon SCVI wild /eggs uses this for all Pokemon properties, right?

On 4/26/2025 at 6:03 AM, SkyLink98 said:

Eggs use Xoroshiro, so technically, calculators that brute-force the seed can be built. That said, the 64bit seeds should provide enough space to allow for all possible PID-IV combinations.

 

Pokefinder cannot be used for eggs in SwSh since it most likely cannot be manipulated?

On 4/26/2025 at 6:03 AM, SkyLink98 said:

In the case of Dynamax Adventures encounters, cryptosecure RNG handles the shinyness. All the other pokemon properties are Xoroshiro. If the cryptosecure RNG decides a Pokémon has to be shiny, the PID gets modified to be shiny, becoming uncorrelated from the Xoroshiro seed.

So modifying the PID to be Xor=1 for it to be shiny, will technically make the PID to mismatch the properties for the pokemon? Since PKHEX does not check for shiny's PID?

[SkyLink98]

10 hours ago, burb00 said:

Pokemon SCVI wild /eggs uses this for all Pokemon properties, right?

Right, ScVi encounters have all the properties generated with csrng, except for raids.

10 hours ago, burb00 said:

Pokefinder cannot be used for eggs in SwSh since it most likely cannot be manipulated?

Most likely yeah, they have no interest in encouraging genners/hackers. Poke Finder is a program made to allow everyone to manipulate the RNG legitimately.

10 hours ago, burb00 said:

So modifying the PID to be Xor=1 for it to be shiny, will technically make the PID to mismatch the properties for the pokemon? Since PKHEX does not check for shiny's PID?

Yeah correct It makes it difficult for PKHeX to reverse to a valid seed with no PID to account for.