On this day last year L4D2 came out. A year before that L4D made us into zombie killing freaks

I found this just now telling about the L4D2 infected and how they have changed from there concept air to the final game play monsters we know and (almost) love

http://www.l4d.com/concept_art/charger_art.html

i lolled at the 2nd spitter and the jockeys looked like children at the start eek