Board games

Crooked Dice — a fair die, a gaff die and a loaded die that look identical

Three 16 mm d6 from one source: an honest die, a duplicate-face gaff showing only 5 and 6, and a die with a sealed void under the 6. Same body, same size, same weight to within a tenth of a gram. Ships the float-test cup that catches the loaded one, and states how crooked each die is as a measured number instead of an adjective — centre-of-mass offset and tipping-barrier ratio for all six faces. A magic and party prop, sold with its own counter-measure.