Here is the full list of all 35 Sudoku Quest achievements.
Complete 1st adventure level.
Complete 1 adventure level without using power-ups.
Complete any adventure level without mistakes.
Complete 5th adventure level.
Complete 10th adventure level.
Complete 15th adventure level.
Complete 20th adventure level.
Complete 25th adventure level.
Reveal 1000 cells.
Reveal 5000 cells.
Reveal 10000 cells.
Fully reveal 50 boards.
Fully reveal 100 boards.
Fully reveal 250 boards.
Fully reveal 500 boards.
Collect 5000 gold in total.
Collect 10000 gold in total.
Have 1000 gold at once.
Have 2500 gold at once.
Complete 5 adventure levels in a row without using power-ups.
Complete 10 adventure levels in a row without using power-ups.
Fully reveal Classic Sudoku with 40 or less givens.
Fully reveal Classic Sudoku with 30 or less givens.
Fully reveal Classic Sudoku with 20 or less givens.
Fully reveal 100 Classic Sudokus.
Fully reveal 100 Nonomino Sudokus.
Fully reveal 100 Overlapped Classics Sudokus.
Fully reveal Classic Sudoku in under 1 minute.
Fully reveal Nonomino Sudoku In under 1 minute.
Fully reveal Overlapped Classics Sudoku in under N minutes, where N is the number of grids.
Complete any adventure level without using pencil.
Finish Classic Sudoku by placing the last number in the exact center of the grid.
Use "Show possible values" power-up 20 times while playing any adventure level.
After activating "Shuffle" power-up fully reveal board in under 30 seconds with at least 5 unrevealed cells.
Reveal first 7 cells in under 10 seconds, starting from first reveal while playing any adventure level.