Just subscribe to this workshop collection and breeze through a hundred planets within minutes to unlock achievements easily: http://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=714397129
These 100 planets are as easy as they can get. You literally spawn on the goal, so each planet only takes 0.1 second.

Before beating the planets, switch to NORMAL difficulty in the game's options.

Play all to unlock 3 achievements:
- One shot: Exoplanet (Beat User Planet in Time Trial)
- Exoplanet Explorer (Beat 10 User Planets in Time Trial)
- Exoplanet Addict (Beat 100 User Planets in Time Trial)

You might even unlock:
- Positive Reality (Top the leaderboard in a User Planet)

Publish and send me a very easy planet and I'll add it to the workshop collection, so anyone who uses this guide gets to play your planet.

http://psteamcommunity.yuanyoumao.com/app/337350/discussions/0/365172547946048677/