Here is the full list of all 28 Tumblestone achievements.
Complete World 9.
Complete World 8.
Complete World 7.
Complete World 6.
Reach rank 25.
Complete World 5.
Complete 25 quests.
Complete World 4.
Solve a 3-star Practice Puzzle.
Get a score of 500 in Infinipuzzle.
Get a score of 333 in Infinipuzzle using a modifier.
Get a score of 1,234 in Marathon.
Empty the board in Marathon.
Complete World 3.
Complete World 2.
Win a Puzzle Race match using a modifier.
Complete World 1.
Complete World 10.
Complete World 11.
Complete the Story Mode.
Solve Puzzle 2-8 using 44 moves.
Win an online Puzzle Race match.
Win an online Battle match.
Win a Battle match against 3 Nightmare bots.
Win an online Tug of War match.
Win a Tug of War match against 3 Nightmare bots.
Get a score of 333 in Heartbeat.
Empty the board in Heartbeat.