The essential experience of Towers and Catapults

I’ve been working on a new game tentatively called Towers and Catapults but the design has changed enough that it no longer describes the game. I’m working with four other people in my advanced game design class. My role is primarily programming but I also do some game design and project management. We’re programming it in C# using XNA and the Farseer Physics library and considering eventually releasing it on XBLIG.

The game is a turn based strategy game where players try to attack each other’s slingshot fruit trees by launching fruit they grow. Players can also use up more fruit and plant a seed on a floating platform which will grow and allow them to get a more strategic position to fire from. The game ends when either side defeats the opponent’s mother tree. Trees take damage when their trunks are hit and their branches act as a shield absorbing damage but will break off if hit hard enough. We’re still tweaking the design so it might change. Below is a screenshot of an earlier build which is still missing a lot of core gameplay.

Early development screenshot

We came up with this idea by thinking about the essential experience we wanted the player to have. Jesse Schell, in his excellent book The Art of Game Design: A Book of Lenses describes the essential experience to be something every designer should focus on because games like architecture are all about the experience. The experience we decided to go with is the fun of launching a slingshot. This particular experience was proposed by me thinking back how I would create catapults out of Lego to launch blocks across the room.

The experience can be broken down into three components or phases. Setting up the shot by pulling back to adjust angle and power. The projectile flying through the air creates anticipation. When the projectile lands it interacts physically with whatever it hits. We were able to confirm with playtests that these phases not only exist but they are incredibly fun if done right.

The stages of the essential experience

We looked at what kind of catapult to use and decided on a slingshot because it has more degrees of control than a trebuchet.  Then we looked into the properties of rubber bands to see if  any of that could be translated to gameplay. Heat makes the rubber band contract; if you stretch it, it creates heat. It’s used to launch air crafts and also as a motor for toy planes and boats. Our final idea didn’t incorporate these points but I thought it was worth mentioning.