Infernal Breeding is a ritual available to all ages of Abysia, that requires Blood 3 to be researched. Casting it requires 2 and consumes 25.

By casting the spell, a number of hell spawn are created. Unlike regular Cross Breeding, units created by a single cast of the spell will be the same unit type, but have an extremely large age variance (making some of them usually suffer old age penalties) and with some number of starting afflictions. Additionally, some unit types may generated with a commander of the same type. The chances of the different outcomes appear to vary in a rather unpredictable fashion based on era and scales¹⁾. Of note is that Luck 3 and Misfortune 3 both appear to be better than neutral luck scales for generating certain unit types.

The Adept Cross Breeder ability has some effect on this spell. It is inconclusive whether this significantly affects the probabilities of creating the different types of hell spawn. However, testing with a bonus of 20 was observed to double the base number created without any effect on the die roll.

Each unit type has an "infernal breeding multiplier" listed in the mod inspector, though it is unknown how this relates to the actual number of units created.

The spell can create the following units:

Image	Unit	Abilities	Probability variation	Commander	Starting afflictions	Additional notes
	Hell Spawn	Fire Resistant (25) Heat (6) Fire Power (1) Undisciplined Animal Flying Wasteland Survival	Decreases with Era progression	Never	25%
	Hell Spawn	Fire Resistant (25) Heat (6) Fire Power (1) Undisciplined Darkvision (50%) Wasteland Survival		Always	50%
	Hell Spawn	Fire Resistant (25) Heat (3) Darkvision (50%) Wasteland Survival		Always	50%
	Hell Spawn	Fire Resistant (25) Heat (3) Darkvision (50%) Wasteland Survival		Always	50%
	Hell Spawn	Fire Resistant (15) Poison Resistant (15) Undisciplined Wasteland Survival	Markedly increses with Era progression	Never	50%
	Hell Spawn	Fire Resistant (15) Poison Resistant (15) Undisciplined Wasteland Survival Flying	Markedly increases with Era progression	Never	50%
	Hell Spawn	Fire Resistant (15) Poison Resistant (15) Undisciplined Wasteland Survival	Markedly increases with Era progression	Never	50%
	Hell Spawn	Fire Resistant (15) Poison Resistant (15) Flying Wasteland Survival Flying	Markedly increases with Era progression	Never	50%
	Hell Spawn	Fire Resistant (25) Heat (6) Fire Power (1) Undisciplined Darkvision (50%) Wasteland Survival	Markedly decreases with Era progression	Always	50%
	Hellbred Giant	Fire Resistant (15) Darkvision (50%) Gluttony (10) Wasteland Survival	Markedly decreases with Era progression	25-30% in EA, otherwise never	50%	EA produces significantly more per cast.
	Hellbred Horite	Fire Resistant (15) Cold Resistant (5) Mountain Survival Wasteland Survival	Markedly decreases with Era progression, can never be obtained in LA	Never	50%