Rixixi have several subspecies - you can read about their unique anatomy and culture at Species Info, but this page is dedicated to their genetics.
Each subspecies other than Standard has genetics inherent to their species - these won't appear in their genocode, but have a chance of passing naturally when bred to other subspecies. Additionally, some - but not all - subspecies can pass genes at random regardless of whether they have the gene or not, and these can pass to their own subspecies as well - for instance, Domestics can pass any color mutation, and Funeraries can pass Ghost.
There are three different ways to breed for a specific subspecies! The specific methods for Combo Mutation breeding will be listed in their tab, as that can differ, but the basic idea is as follows:
Method 1: If a Rixixi has 5 or more mutations in one category (Color, Combat, Volatile, RXX-NOMALY), this has a 20% chance to combine (much like combination mutations) and cause a subspecies to appear in a breeding without that subspecies.
Method 2: Some subspecies appear when a specific combination of mutations appears instead of any 5 in a category - usually this requires fewer mutations to activate due to being specific.
Some Supercharged Fogshards can alter the subspecies of a Rixixi:
Illusionate-Glass Cores add an alternate form, typically of a different subspecies.
Moddable | Primal | Domestic | Mechanix
Your average modern Sxriix'n. As this is the standard Rixixi, this tab effectively serves as a template.
An ancient subspecies of Rixixi, evolved separately from the modern Standard subspecies while hidden away from the world. Massive and bulky.
A subspecies that went through a program to look more feline and harmless to blend in on Earth. Small and cute.
Rixixi adapted to the Leyline, having lost their faces and become supernatural beings.
A hybrid between Primals and Domestics. Small, but still bulky.
As a Hybrid Subspecies, instead of just passing their own subspecies at a 50% chance (with the other subspecies in the breeding taking up the other 50%), Dwarf Primals have a 30% chance to pass Dwarf Primal, a 10% chance to pass Primal, and a 10% chance to pass Domestic.
Manticores are humans that are heavily body modded and genetically spliced with Rixixi. They require the Manticore Vat item to breed with Rixixi, unless the Manticore is a starter.