Subquest

If each of five paths through the game has an entirely independent set of locations, monsters, spells, characters, subquests, and game objectives, the designer is essentially faced with creating five wholly different games.

This is an example of a subquest that must be completed before the main one can be finished. Or the subquest could be finding a key that unlocks the room holding the princess since the room has been magically sealed against all entry without the key.

The quest is broken down into a number of episodes that progress in a linear sequence, each with its own subquest and major challenge at the end.