It was the first in the series to use ragdoll physics and featured cutting-edge tech like normal mapping, HDR lighting, and heat/water distortion. Multiplayer and Cooperative Modes

Departing from earlier linear "corridor" levels, Chaos Theory features larger, non-linear environments with multiple paths and optional secondary objectives.

A 2v2 mode where third-person spies attempt to hack objectives while first-person mercenaries defend them with lethal firepower.