The story
Originating from the tabletop wargame Warhammer 40,000, named after the Tyranid Carnifex, a visually imposing and relatively tough monster model that has a low point cost.
Etymology from Wiktionary, CC BY-SA 4.0.
distraction carnifex
Today it means: A cheap, visually imposing unit sent out in order to draw fire from the enemy, allowing other units to perform objectives safely. Full definition →