Here is the full list of all 20 Pool Nation achievements.
Won 8 Ball Tour
Win One Game In All Rule Sets
Reach 1500000 Points
Reach 12 minutes in Endurance
50 ball streak in Endurance
Won 9 Ball Tour
Use a Flashback
30 Ball Streak in Endurance
Reach 8 minutes in Endurance
Clear the table in Endurance
First Win Against AI in Versus
Reach 4 minutes in Endurance
Win First Star in Tour
Earn 5000 points in one skill shot
Earn 10000 points in one skill shot
Win First Bonus Match in Tour
Obtained all 298 stars
Win Online Tournament
Win Online Match
Reach 20 minutes in Endurance