Instead of your typical up and down to move forwards and backwards, left and right to tilt you use the left and right arrow keys to control hydraulics that make it take a little more skill to tilt your huge rig.
You are a mountain rescue truck and you have to get to the shelter as quick as possible but theres a twist. You're a big heavy vehicle so you have a big heavy engine attached behind you. You have to navigate through the Mountains with that heavy load. Think your up to it?