Here is the full list of all 16 Flipon achievements.
Reach a x10 multiplier
Complete a challenge level
Defeat MadMatik
Complete a puzzle level
Defeat the Space Sheriff
Complete a survival level
Complete an objective level
Defeat Loméo
Defeat the greed pyramid
Defeat the Golden Phoeniux
Reach a x20 multiplier
Reach a x30 multiplier
Chains 10 combos with a single action
Wins all encounters with Piratou
Read the credits. Entirely. It's important for the people who makes game to be properly credited.
Complete the bonus levels