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