IEDs. Back before we learned we’d keep convoys not at set distances. Ie, 50 meters between trucks.
Haj would set up a stake about 50 meters from the IED and a stick at the IED.
First truck goes by and they count their “Allah Akbars.” If it’s 3, then when the second truck goes by Haj counts 3 Allah Albars and then WHAMMY.