Here is the full list of all 45 Flagsplosion achievements.
Reach a score of five in Endless Reverse
Earn twenty gold stars on a flag.
Complete both Canton mode and Un-Canton mode without any wrong answers
Complete Canton mode
Earn ten gold stars on a flag.
Reach a score of ten in Endless.
Solve a flag on its birthday.
Earn nine gold stars on a flag.
Unlock one hundred flags in the Encyclopedia.
Unlock fifty flags in the Encyclopedia.
Earn eight gold stars on a flag.
Earn seven gold stars on a flag.
Play Endless Mode.
Gain gold on all training levels.
Complete one hundred training levels.
Unlock a hidden bonus game mode.
Complete fifty training levels.
Complete twenty-five training levels.
Complete ten training levels.
Complete a training level.
Earn six gold stars on a flag.
Earn five gold stars on a flag.
Earn four gold stars on a flag.
Earn three gold stars on a flag.
Correctly solve eight flags with red in a row.
Earn two gold stars on a flag.
Earn a gold star on a flag.
Unlock your first flag in the Encyclopedia.
Choose incorrectly on a flag that has its name on it in big letters.
Unlock two hundred fifty flags in the Encyclopedia.
Unlock all flags in the Encyclopedia.
Reach a score of twenty in Endless.
Reach a score of thirty in Endless.
Reach a score of forty in Endless.
Reach a score of fifty in Endless.
Reach a score of one hundred in Endless.
Unlock five hundred flags in the Encyclopedia.
Have a gold star on the flags who have a single gold star.
Reach a score of ten in Endless Reverse
Reach a score of fifteen in Endless Reverse
Reach a score of twenty in Endless Reverse
Reach a score of twenty-five in Endless Reverse
Reach a score of fifty in Endless Reverse
Finish with a score of twenty-five or more in Endless Hard or Reverse Hard
Play every mode in Flagsplosion