Star Child

Nimrod knew and remembered that, although the Emperor genuinely had humanity's best intentions at heart and didn't care for glory or acclaim, the Emperor was a rotten bastard plated in gold. Should the Emperor successfully consume Nimrod's soul, Nimrod's lack of psychic experience would leave him broken on the Emperor's anvil, easily broken down for whatever selfish wish the Emperor had. Thus, if Nimrod was going down, he'd take the Star Child with him; one godly shard was as good as the next, and the Emperor had a dozen of the bigger ones. Moreover, it just so happened that Nimrod remembered a piece of lore about a kid giving off Emperor vibes and rumours of the Star Child's reemergence into the setting.