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.

Reason #3: It's Ride or Die time
With a game world as big as this, you don't want to be plodding around on foot. Luckily, there are vehicles everywhere. Civilian pick-up trucks line the roads and armoured trucks can often be found at enemy bases or, of course, you can just shoot occupants out of ones in use.

An armoured vehicle's mounted gun is powerful enough to blast helicopters out of the sky, which is handy if you've run out of grenades in your launcher. While choppers themselves aren't flyable in single player, they are in multi-player. As are the hovercraft.

You can also dive into tanks and other armoured vehicles, plus the odd boat. Keep your eyes on the on-screen icon indicating how much damage it's taken though. Once completely red – usually at about the point you can't see through the windscreen for bullet holes and blood smears – it's a good idea to leap out before the inevitable explosion.