Based on the earlier ramblings about entropic and finite concepts, here is a coarse concept: An empty level that is literally torn in twain. There is a rather staid camera setup that is based on the characters distance from one another, largely highlighting, at first, the vacuity of the environment and later, based on which sides of the divide the characters find themselves, the distance drawn between the characters and the hopelessness of their situation.
The Prop, which may or may not be a tree, is a rallying point at first, and later something to watch die before them, and pehaps rescue.
The ground will tear along a predefined animation, not dynamically. The whole experience will take about five minutes.