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