Ashfall Rising. Astra Echoes, #0.2

When a ghost signal reaches Somnia Magna from the edge of Praetorium-controlled space, Captainr Vivian Hayes knows it cannot be ignored. The voiceprint belongs to a legendary resistance synthetic who vanished seventy years ago. His message is damaged, incomplete, and already five years old - but what remains points to Sacramentum, a sealed world of ash, deorum, and official lies. With only two trusted companions, a fragile ship, and no promise of extraction, Vivian crosses into enemy territory to uncover what Praetorium has buried beneath the surface.
But Sacramentum is not a dead world. Something is still active there. Something powerful enough to shake the planet, draw the attention of dangerous people, and change the future of the rebellion. Set before the events of the Astra Echoes Series, Ashfall Rising is a tense science fiction novella about resistance, loyalty, hidden truth, and the cost of answering a call that should never have survived the dark.