The Sun and Moon

System One consists of the first 20 levels in the game plus boss level I. These levels are all relatively simple and introduce you to the basic concepts of the game - platforming and phasing. Remember that there is no time limit for completing levels for this achievement, so take your time so you don't die needlessly over and over.

All of the System One levels are very straightforward, and will build up the core concepts and techniques you need to be familiar with. The boss level adds a white ball that chases you around the level. Don't worry, you can outrun it and jump over it easily. Just make sure to dodge it while collecting the five dots. 

Upon completing all 20 levels and boss level I, the achievement will unlock.