Runner 2 is divided into five themed worlds, each with fourteen regular levels and five bonus stages. This makes a grand total of ninety-five levels. There are also an additional 25 Retro levels (120 total levels), but those are not needed for this achievement. Those are triggered by touching a Yellow cartridge in the level.
You only need to defeat the BOSS at the end of the world to open the next world. There are checkpoints halfway through each level and after each phase on a boss level. You do not need to get a perfect to pass a level (but you should go for it if you are interested in the other achievements).
Five Worlds
1. Welkin Wonderland
2. The Emerald Brine
3. The Super Nature
4. The Mounting Sadds
5. The Bit Trip
TIP: You can change the difficulty to "Quite Easy" and just make it through the levels to progress through the game, although Perfect and Perfect+ are needed for other achievements
You receive your achievement by defeating the BOSS at the end of The Bit Trip World in the level "Flight to Fate."