You play as a tree growing from a seed. The choice is whether to grow upwards or sideways. Growing sideways makes your tree wider so that you collect more sun-light and can grow faster. Growing upwards allows to overtake competing trees. Trees that are taller than others can grow sideways to block sunlight to their competitors.
If you decide to use this idea could you please put a link to LoseTheGame.com somewhere in the intro/credits and email us at mail@losethegame.com thanks 