#euclid cipher

why did you do it?

[Image description: art of Bill Cipher. He's floating in a dark void, illuminated by blue light from the bottom upwards, staring forward with his eye wide, and with his limbs hanging limp. Behind him is a white panel shattering into pieces, showing a red and a blue triangle holding hands. A smaller triangle between them has been punched out of the panel. On the very bottom of the canvas blue flames produce light and white squares simulating a "pixel glitch" effect, on the opposite end, there are white dots adorning the void, gradually disappearing downwards, simulating stars. End ID.]