FFA is deathmatch stripped of its last restriction: teams. Anything that moves is an enemy, allies do not exist, and nobody will ever cover your back.
Your head learns to swivel here: minding your rear beats raw accuracy. After half an hour of FFA you start catching footsteps in classic mode that used to fly right past you.
Play this mode →Maps for the modes live in the map catalog, guides in the blog, and your look in the models gallery.