Here is the full list of all 16 Tetradecagon achievements.
The illusion of allusion.
Suck 500 times.
Use the Konami Code.
Beat your highscore 50 times.
Die 100 times.
Beat your highscore 10 times.
Enable epileptic friendly mode.
Lose control of the ball seconds immedietely after bouncing it.
Beat your highscore.
Die 5 times on one level without progression
Perform a 360 while bouncing the ball.
Perform a 540 while bouncing the ball.
Die for the first time.
Die immediately after the grace period on the first level.
Beat the highest level, Icosagon.
Glitch the ball out of the polygon.