Egg Groups are biological categories that Pokémon species are slotted into that determine which species can they interbreed with. The mechanical details of egg groups in the franchise mainline are at Egg Group.

Pokémon are slotted into the following egg groups as of Gen Ⅷ:

[1] “Undiscovered” is also called the “No-Eggs” group.

A given evolutive stage can belong to up to two (2) Egg Groups.

This categorization introduces a number of problems because there is no clear distinction between the various values and Pokémon can belong to more than one at a time, for example the fact that Anorith can interbreed with Archen despite they belonging to entirely different clades, as well as the infamous “Hot Skitty on Wailord Action”.

In the Suocéverse egg groups are somewhat more restricted, and even then in the wild breeding is restricted to one's own species, with most cases of inter-clade breeding only being viable in laboratory conditionsMainlinein tailored societal conditionsNrafhal.

For Suocéverse mechanics, a species is related to at least one (1) egg group, with no technical higher cap; however most species have one related egg group. Egg groups are an aspect of the species; the fact that a given evolutive branch or Pokémon “node” is not breedable is a condition separate from the fact that it “belongs” to a given species and shares its breeding traits.

This canon also adds new egg groups and reworks existing ones, with the purpose of having a more sensible and restricted reproductive relationship between species. Each new group added is based on a number of distinctive factors to filter some species from their originator egg groups listings:

• In the source monster covered anything vaguely reptilian in nature. This is now reorganized across different groups:
  • the monster/kaiju group filters from the general “vibe” and selects mostly for body shape upright.
  • the saurid group which mostly covers small snakes and lizards, that don't really enjoy the “monster” or “kaiju” contexts that the original group had, and selects promoting from the body shape squiggle.
• Originally field covered anything mostly non-reptilian that lived on the ground (hence the original ident ground). This meant it was a sort of “default bin” for egg groups as pretty much anything “animal-like” could end up there. This is now reorganized across different groups:
  • field itself is reorganized into a “mammalian” or “cydonian” group, which covers mammal-like Pokémon.
  • the saurid group into which some snake or turtle-like creatures are recategorized;
  • the terrarian group which selects those creatures that live mostly or fully underground or in “underworlds” and are specifically adapted for that.
• Originally mineral covered anything that was “vaguely resembling an object”, even in the cases where those had an obvious or predominant organic component: compare eg.: Snorunt, who lives inside an inorganic shell, Frigibax who is fully organic, and Honedge who is literally a possessed object. This is now split into:
  • mineral itself, now rebranded as inorganic.
  • a special animate group that covers those Pokémon that “exist” by possessing or imitating an object, and thus would have a a reproduction system wholly unlike that of organic creatures, if having one at all.
• The fungi group is split off from plant to account for the vast organic difference between plants and fungii in general.
• The specific (or restricted) group is split off from undiscovered (“no.eggs”) to account for the difference between Pokémon species that are actually unbreedable vs. species whose breeding mechanics are restricted down to only or mostly their own species, or a specific set of species, such as some minor Legendaries.

The list of Egg Groups in the Suocéverse as of last edit of this article goes as follows: