Here is the full list of all 22 M.I.A. - there are Overture achievements.
start scene
beach scene
cave scene
center scene
end scene
6666gold
15000gold
50000gold
100gem
1000bullet
100plant
Complete the first puzzle
Break the stone under the ship
Complete the Shooting puzzle in Beach stage
Complete the Reflect puzzle in Cave stage
Complete the Joystick puzzle in Cave stage
Find all 4 keystone in Cave stage
Complete the Projection puzzle in Cave stage
Complete the Trinity Ring puzzle in Bighole stage
Defeat the last boss
Fall into the hole in Bighole stage
This is a secret achievement in the last scene