Needs a better introduction. :/
In some video games, mainly platformers, there is a type of level that involves traversing the same terrain, but in different forms - one for each season of the year. For example, one might progress through the "spring" version of the level, then the "summer", "fall" and "winter". This often involves going through a door to travel from one season to the next. Such levels often use the seasonal varieties to create slight changes in each version of the world - for example, a lake in one version might be frozen in the winter version.
For some reason, this is most likely to be a forest/woods-themed level. Possibly because it's much easier and visually dramatic to show the differences between, say, spring, summer, fall and winter when the leaves (or lack of) on the trees are different for at least 3 of the seasons.
- Made into a core game mechanic in The Legend of Zelda: Oracle of Seasons. Swinging the Rod of Seasons while standing on a stump causes the seasons to change, making various paths open and close (water freezes and leaves fall off certain trees in winter, baba buds bloom in spring, et cetera).
- Kirby Super Star has a planet that hits all the notes of this trope. The setting is woods-based to a degree, there are lakes that are frozen in the "winter" form, and the player switches seasons by entering a door.
- The NES game Mickey Mousecapades features a woods-themed level that merely uses a Palette Swap to differentiate between spring (purple leaves on trees), summer (green leaves), fall (brown leaves), and winter (white leaves, white snow instead of green grass, and the path now looks like ice). Doors take the player between seasons.
- Banjo-Kazooie has a very large level that uses this trope, and again, it's forest-themed. A giant tree, with inhabitants such as a squirrel who collects nuts for the winter, serves as the focal point.
- In Sonic 3 And Knuckles, judging by the colors, Mushroom Hill Zone Act 2 briefly beings in summer, but soon transitions into autumn, with everything being orange. Halfway through, the grass and tress turn grey to signify winter. At the end of the level, you destroy a satellite and things return to summer in time for the Boss Battle.
Any more examples?