NPCReplacements=(FromClassName="Ichthyornis_Character_BP_C",ToClassName="Dodo_Character_BP_C")
NPCReplacements=(FromClassName="Pegomastax_Character_BP_C",ToClassName="Lystro_Character_BP_C")

-OR-

DinoSpawnWeightMultipliers=(DinoNameTag=Ichthyornis,SpawnWeightMultiplier=0.1,OverrideSpawnLimitPercentage=true,SpawnLimitPercentage=0.01)
DinoSpawnWeightMultipliers=(DinoNameTag=Pegomastax,SpawnWeightMultiplier=0.1,OverrideSpawnLimitPercentage=true,SpawnLimitPercentage=0.01)