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