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