Satchel Charge Fell Through Floor - Apprehension

At the very beginning of Apprehension where you encounter the first zombie, I through down a satchel charge and it went through the floor.

Founded in 2004, Leakfree.org became one of the first online communities dedicated to Valve’s Source engine development. It is more famously known for the formation of Black Mesa: Source under the 'Leakfree Modification Team' handle in September 2004.