More Tomato Ketchup And Mustard Gas (My Very Best Friendly Fire)Transit, Mechelen, Belgium September 2006 i Tomato ketchup is a popular condiment, used also as fake blood in children's games. Mustard gas is a vesicant chemical warfare agent with the ability to form large blisters on exposed skin. Friendly fire is a term originally adopted by the United States military in reference to an attack on friendly forces by other friendly forces. Tetra Brik, carton packaging with a metal layer inside, for milk and other liquid products, is a popular material for thermal isolation on the interior walls of shanty houses. 1 / 5