Post mortem
We made Left for dead as a paper prototype. I myself havent played the game but most people in the group knew the game very well and its not hard to figure the game out. You run and kill zombies and get guns, ammo, health.
The objective of the game is to survive.
Our game was alot of fun to play when we tested it. It wasnt that balanced, and much was based on luck. We didnt have the time to change that significantly so it still was when the time was up.
That was the critique we got as well. So all in all it worked out fine. Our work strategy was just to get a game fast, and then test and change stuff until it was good enough. The time then ran out on us so the game only got to like 2/3 of what we wanted it to be but it was alright knowing that we were on the right track and that we probably can do it better next time.