QED Night is a puzzle site: a daily brain-teaser, a collection of logic puzzles, and hidden-role party games. The name comes from quod erat demonstrandum — "that which was to be demonstrated" — the line a mathematical proof ends on. It's there because of the one thing we don't ask you to take on faith: every logic grid, zebra, and knights-&-knaves puzzle here is checked by a constraint solver before it's published, which tries every possible arrangement and confirms exactly one of them satisfies all the clues. The ∎ badge means that check ran and passed, not that we think the puzzle is good.
QED Night is operated by Cassau LLC.
Questions, bug reports, or a puzzle that doesn't check out — email chaudai621@gmail.com.