Unlimited time.
You are a giant Monster pissed off smashing the city! Smash all the buildings , planes, people and cars specified for each objective. Light things on fire or kick them till there is nothing left. You can also just play sandbox mode where there is not time limit. Take some anger out and play City Smasher!
Use the ARROW KEYS to walk, SPACEBAR to jump. Press "A" KEY to kick and "S" KEY to smash. Combine UP ARROW and "A" KEY to throw some people and cars in the air. Who knows .. maybe you will hit some planes down. Combine DOWN ARROW and "S" KEY for fire smash. Good luck!