Space Master Achievement in Hexologic
Complete cosmic special levels
How to unlock Space Master
There are three Cosmic special levels that unlock after you've completed puzzle #75 of the basic levels. You can access them by selecting the hexagon icon to the left and between puzzles #74 and #75.
Note: There is a fourth level in this group, accessed by selecting the hexagon marked with an infinity symbol. This level is not necessary for any achievement.
Refer to "Hard Mode Totems Master" for more information.