Here is the full list of all 15 Primeval achievements.
Early Access Adopter.
Traveled 500+ hexes.
Traveled 1000+ hexes.
Spawn 50 Hydras.
Win against a total of 50+ players.
Win against a total of 100+ players.
Win against a total of 250+ players.
Win against a total of 500+ players.
Summon 500 Skeletons.
the Destroyer of Worlds
Destroy 250 Units.
Destroy 500 Units
Destroy 1000 Units
Inject a total of 250+ poison
Thanks for Nothing!