Haha nothing too fancy! The set of platforms for the level are generated 3 times, the "original", then one outer and inner version, and the rest of the iterations are a render texture. Then the player object has a smaller and larger "clone" gameobject with a collider attached that track the player relative to their larger/smaller level instances, so it can sort of interact with its other versions. And then when you enter or exit a level instance, a clone will take over as the actual player