u/Certified_Cichlid

Wandering Nobles, Elden Ring. They are biologically immortal, but they absolutely can be killed. They are cursed with eternal life but they don’t revive if they are killed, other nobles take their place. Only the tarnished could revive as a power. This extends to all soldiers and animals which seemingly respawns but those are merely other soldiers and animals replacing them.

TLDR Elden Ring NPCs can't die from aging but can be killed.

Viltrumite interbreeding. Viltrumites would not and could not reproduce with any organism. To reproduce, the mate is required to be a member of a sapient race, preferably humanoid. The more the race resembles themselves the stronger and closer to a pure blood Viltrumite the offspring is. What they have is dominant genetics in appearance when reproduction is viable, not be able to reproduce with literally anything. Hybridization between aliens aren’t unique to Viltrumites either.

TLDR Viltrumites have dominant genes but can only procreate with sapient species.

Talescrian soldiers appear to have human body form and digits. We haven’t seen their faces but it could be presumed they are a human-like race.

Power discrepancy is greater in season 4 finale than season 1 finale.