Reason #2: The enemies are idiots
Crysis' AI credentials have been bigged up from the start of its development. Not only do enemies use cover and flank the player, they understand their environment. Objects in the game world are programmed to communicate with them, so the AI knows it can jump over a wall or use a recently flattened tree for cover.
“We have smart object interactions, so if an enemy encounters a fence, he knows he can jump over it instead of running around it,” says Hubler. “We've programmed it so enemies can sometimes fall over too. You have moments where you're thinking 'damn he's going to kill me'. Then he trips over and you kill him instead.”
Equally as impressive as this unpredictable and downright clumsy behaviour is how the Korean soldiers react to your character's futuristic US prototype Nanosuit and its various cloaking and super-speed abilities. Understandably, seeing as they've never seen anything like it before, they react with surprise and confusion at the sight of a man darting towards them like Linford Christie on fast forward. If you're seen running down a dead end, then you activate the suit's cloaking function, enemies understand that you can't have disappeared into thin air and respond by tentatively investigating the area.
