I was wondering if it got harder or if it's just random: function generateColors(difficulty, blacklist) { ... let sample = Math.floor(Math.

I was wondering if it got harder or if it's just random: function generateColors(difficulty, blacklist) { ... let sample = Math.floor(Math.min(Math.max(0, 1-Math.pow(1-difficulty, 1.5)), .99)*5); let distance = (5 - sample)/5; ... } function setupRound(blacklist) { ... const data = generateColors(currentRound/totalRounds, blacklist); ... } Plotting that first magic: https://lucb1e.com/randomprojects/js/testformula.htm#%24%28%27formula%27%29.value%3D%27Math.floor%28Math.min%28Math.max%280%2C%201-Math.pow%281-difficulty%2C%201.5%29%29%2C%20.99%29*5%29%27%3B%24%28%27vars%27%29.value%3D%27difficulty%3D0.0-1.0i0.05%27%3B https://lucb1e.com/randomprojects/js/testformula.htm#%24%28%... round# difference 0-- 2 5 3-- 5 4 6-- 9 3 10--13 2 14--20 1 The "blacklist" parameter prevents that you get the same challenge twice. Note also that it submits every answer to the server (fine imo, but I think it would be even nicer if this was mentioned on the page)