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