<b_jonas> slashlearn euclid//Euclid is a short geeky game in which the goal is to do Euclidean compass and straightedge constructions in as few steps as possible. It runs in the browser, found at "http://www.euclidthegame.com/". It was popular among #esoteric regulars in 2016-07.

You're in a 20 foot by 20 foot stone room. A stout oaken door banded with iron affords the only visible egress. As you approach the door, an imp appears. "Hello, INSERT NAME. To pass, you must solve my puzzle. SEE HANDOUT 1 ON PAGE 17."