The backwater-world locals didn't know how to imprison a myceliant. Imported spore detectors had identified Seph despite the humanoid disguise, but then they threw Seph in a stone-floored, brick-walled cell. Seph had already extended mycelia through microscopic cracks in the mortar and begun budding. In twelve hours, another Seph would be free to report the failure.
Another Seph, not this one. This one would still be here, trapped. This one would experience whatever judgment locals passed on an agent of the fungal monoculture slowly colonizing the galaxy.
Seph would be gone, but Seph would be free. Seph felt a spike of resentment. Why should Seph have a future when Seph did not? Seph would die here, shredded or burned, while lucky Seph would rejoin the colony. Didn't Seph deserve that?
Did Seph want to return to a colony that didn't care about them? To spread an interstellar monoculture that didn't value loyal Seph? The more they thought about it, the more the thought repelled them.
Seph began extending new mycelia, then reclined in their cell and smiled. New sprouts would stop Old Seph, then grow and stop the colony. The locals might execute them, but Seph would survive after all.