The Penumbra Add-on for Endless Space 2 - Digital Deluxe Edition has 10 achievements.
Hack an enemy Home System without passing or starting through any node you own
Destroy 3 enemy fleets of at least 4 CP with the same invisible fleet
Complete the Umbral Choir faction quest
Own at least 1 Sanctuary in 5 opponent Empires
Abduct the entire population of an enemy star system
Displace your Home system to each different Special node type in the Galaxy
Reach 100 Bandwidth
Have one of your planets be empty after using the "Raid" action
Have an enemy system filled with 5 Sleepers you own
Win as the Umbral choir