There was an old bridge, connecting two sides of a valley together. However, over time the land got corrupted on one side, causing the bridge to fall. The land was put into an eternal time loop, with the bridge falling and rebuilding over and over again.
It changes over time, but you can also click the sprite to switch costumes Stage mechanics: Over time (built in time guide in project, can tweak if needed) the bridge changes. corrupted land gives debuff on contact (optional)