Imagine you are a soldier Llama is this jolly enough Christmas shirt in a Roman Legion under Marcus Licinius Crassus during the Spartacus Uprising. Your forces under Mummius have failed to subdue Spartacus at Bruttium and the next day the cohorts are lined up by your officers. You have no idea what is happening but you and your entire cohort have just been separated into groups of ten.
Your Praetor announces that due to your commanding officers disregard for my command and your lack of courage and discipline in battle against slaves no less you will be punished by Decimation. The ranks grow quiet some know that this will mean the end. As everyone in your group grabs a stone you open your hand to see this
You sigh from relief Llama is this jolly enough Christmas shirt but you look over at your best friend staring petrified at his hand because he grabbed the white stone. Now you and the other eight who got black stones were given clubs and ordered to kill your best friend or you all die. You and the other beat your friend mercilessly until his brains are out on the ground. You wipe off the blood from your face and hear the countless screams around you and after a while the screams go silent. men were slaughtered by their own comrades that day.