Here is the full list of all 12 Minesweeper Extended achievements.
You've won 10 times!
You won without using any.. mines?
You've cleared the smallest board size!
You won without using any Flags!
You've cleared the largest board size!
You beat a game in under 5 Minutes!
You beat a game in under 2 Minutes!
You beat a game in under 1 Minute!
You got your first Win!
You got you first Loss!
You've won 50 times!
You've won 100 times!