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