<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.

fizzie is not fnord with a monad but the king of #esoteric, see https://zem.fi/static/img/square_fizzie_320px_white.jpg . He understands how it actually works.