Here is the full list of all 17 RUKIMIN's Disappointing Adventure! ~SHOBOMI AND THE PHANTOM RUINS~ achievements.
Beat BLOCK KING!
Died 50 times
Died 10 times
Died once.
Game over on the title screen.
Game over on the game select scene.
Overflowing from the screen.
Died 100 times
Clear with less than 5 deaths
Eat rice balls
Beat BLOCK KING! ver2.0
Meet a PRINCESS BELL!
Returned to the starting point.
Completed faster than 10 minutes.
Finished the tutorial.
Completed the mission.
Falling walls hold secrets.