Spectrum Stories are probably the single most popular method in modern games to solve the “Sandbox Paradox”. The basic rundown goes like this: during the entire course of the game, the player will be presented with many (sometimes hundreds) of opportunities to make choices. By far, the most common flavor is “spare bad guy” vs. “kill bad guy”. Sometimes a variant is “just kill everyone” vs. “be stealthy and try not to kill anybody”. Every time you make a choice, it nudges your standing on some greater spectrum.
Usually, this spectrum is a moral one (good vs. evil), and results in a different ending depending on how ‘good’ or ‘evil’ you were during the game. Occasionally, your current standing on the good vs. evil spectrum will also determine some of the powers or items you will have access to in the game.
“Spectrum Stories” are those in which many choices ‘accumulate’ over the course of a game to unlock a particular direction.
There aren’t any inherent downsides to using the spectrum itself, but current implementations leave a lot of room for improvement. The biggest complaint with accumulated choice stories is that the only place that your actions tend to have an impact is at the very end of the game. Thus, the player’s true impact on the story usually lacks any ‘bite’ until the very last cutscene. They also tend to trivialize moral choices by casting decisions as clearly good or evil.