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