Difficulty

Difficulty in vanilla Celeste is never defined; instead, B-Sides are naturally positioned as harder than A-Sides, with C-Sides being a notch above both. Farewell's difficulty is slightly above the C-Sides themselves. However, mods have a much greater flexibility when it comes to difficulty, and as such, several difficulty scales have been developed for the purposes of modding. Here are a few examples.

Spring Collab scale

The Spring Collab scale is one of the most common ones used in the Celeste community: it effectively divides maps into five broad categories, furthermore adding modifiers in order to indicate whether it is easier or harder than the average in said category. These difficulties are generally defined by techniques used instead of anything else; however, sufficient use of a given technique can propel a map into a harder difficulty, even if a given map does not use tech associated with a specific difficulty.

Beginner

Beginner difficulty, unlike what it may seem, is not necessarily what is typically regarded to as "beginner" in most other games. Most of Celeste's base game chapters fall into this beginner category, especially the A-Sides but arguably some B-Sides as well. Some simple tech, such as Dream Jumps, fall within the scope of beginner difficulty. Beginner maps generally do not have too many tight jumps, and seldom use more advanced techniques.

Intermediate

Intermediate difficulty maps feature the introduction of some tech, notably hypers, wavedashes and wallbounces. The precision featured is higher than in beginner maps, but is still relatively lenient compared to higher difficulties. Most of Celeste's B-Sides and C-Sides fall into this category, alongside much of Farewell.

Advanced

Advanced difficulty maps are a relatively small step up from what Celeste's base game has to offer. Reversed tech and neutral jumps are introduced at this difficulty level; the level of precision expected from Madeline also grows significantly higher. Generally speaking, a player who has completed Farewell once shouldn't have too much difficulty picking up the tech used in advanced maps. Some Farewell and C-Side rooms can fall into this category, but that's about it.

Expert

Expert maps are where things truly start becoming difficult for many. Techniques such as dream hypers, cornerboosts and ultradashes are introduced at this difficulty. These maps generally feature very high levels of required precision, and require at least some degree of mastery with Celeste's various tech in order to complete. No Celeste base game level will bring you to this difficulty.

Grandmaster

Grandmaster maps are some of the hardest maps available in Celeste, and are generally limited to top-tier players. These maps feature advanced tech almost consistently, including chained ultras, spike jumps and core hypers. Deep knowledge of the game and consistency at frame-limited (≤ 4 frame) tech is expected at this level.