Post
The amount of difference a game can afford before randomness turns into mush.
Run variety budget is the controlled spread of enemies, rooms, items, events, modifiers, and routes across attempts. Too little variety makes runs blur together; too much makes the game impossible to learn.
Example
Spelunky keeps rules consistent while varying level layouts. The Binding of Isaac leans into huge item variety but anchors the chaos with familiar room and boss structures.
Why it matters
This matters because roguelikes need surprise and mastery at the same time, which are naturally in tension.
Related concepts