The following is a short list changes to the Ranking Criteria and their respective discussion threads as of May 25, 2018. Dates mark when a rule was amended to the wiki
5-25-2018
- Metadata section of the general Ranking Criteria was fully rewritten ( https://osu.ppy.sh/community/forums/topics/719568 )
- osu!-specific guidelines were majorly adjusted. Multiple guidelines were removed, two guidelines became rules, and one rule became a guideline ( https://osu.ppy.sh/community/forums/topics/717741 )
- Difficulty naming rule was adjusted to permit multiple custom names when the highest diffs of a set are of similar difficulty (plus more loophole insurance -- https://osu.ppy.sh/community/forums/topics/728366 )
6-3-2018
- osu!catch rules and guidelines were majorly adjusted. ( https://osu.ppy.sh/community/forums/topics/725208 , https://osu.ppy.sh/community/forums/topics/725210 , https://osu.ppy.sh/community/forums/topics/725256 )
6-7-2018
- Fix mistake from previous osu!catch changes. One guideline was accidentally placed in the rules section
- Clarify parts of the metadata section of the general RC. Previous metadata amendment overlooked usage of "TV Size" as a term and the romanised title field.
- Add a rule and guideline for game-mode conversion issues. ( https://osu.ppy.sh/community/forums/topics/751411 )
6-11-2018
- Adjusted how Russian is romanised for certain characters in the metadata section of the general RC ( https://osu.ppy.sh/community/forums/topics/756552 )
6-18-2018
- Fixed issues with skin set list and skinning rules ( https://osu.ppy.sh/community/forums/topics/729230 )
- Adapted rules that conflict with default skin elements ( https://osu.ppy.sh/community/forums/topics/759744 )
- Clarifed "TV Size" glossary entry
6-26-2018
- Adjusted taiko bar line definition to align with client changes ( https://osu.ppy.sh/community/forums/topics/766408 )
7-29-2018
- Majorly changed spread and audio requirements for mapsets. Notable differences are loosened drain time relations to required diffs and how song compilation/edits are more strictly handled. ( https://osu.ppy.sh/community/forums/topics/726474 )
- Clarified requirements for hitsound feedback of reverse sliders. In most cases, they shouldn't be silenced ( https://osu.ppy.sh/community/forums/topics/778581 )
- Disallowed unused .osb files. This makes for a more accurate beatmap listing now that storyboard search works again. ( https://osu.ppy.sh/community/forums/topics/777016 )
- Clarified additional red line usage for Nightcore as acceptable. Rule was unclear previously ( https://osu.ppy.sh/community/forums/topics/772442 )
9-11-2018
- Guideline added to prevent storyboard end time mistakes. ( https://osu.ppy.sh/community/forums/topics/784403 )
- Guideline added in response to removal of 2 diff minimum per mapset rule. This essentially makes it so unfitting/inappropriate single diff sets that feedback expressed concerns about aren't allowed. ( https://osu.ppy.sh/community/forums/topics/726474 )
- Guideline added about poor hitsounding with custom samples (osu!/osu!catch only). ( https://osu.ppy.sh/community/forums/topics/744489 )
- Stacking rules for osu! were reworded and guideline for stacking on Insanes was added. ( https://osu.ppy.sh/community/forums/topics/783749 )
10-13-2018
- Exception added to inappropriate submissions rule ( https://osu.ppy.sh/community/forums/topics/811164 )
- Change to set contribution rules. Difficulty count is what determines contribution now, not exact drain time. ( https://osu.ppy.sh/community/forums/topics/804448 )
- Snapping rule reworded to allow songs unsupported by the editor's beat snap divisors. ( https://osu.ppy.sh/community/forums/topics/798129 )
12-8-2018
- Clarify Rules and Guidelines on allowed dashes / hyperdashes of different beat snap in Salad and Rain difficulties. ( https://osu.ppy.sh/community/forums/topics/795538 )
- Guideline added preventing drum sampleset usage in osu!taiko. ( https://osu.ppy.sh/community/forums/topics/817856 )
- Minor change to guideline about rhythm density to osu!taiko's Futsuu ( https://osu.ppy.sh/community/forums/topics/817856 )
- Stacking rule in Hard difficulties clarified. Sliders have more leniency now. ( https://osu.ppy.sh/community/forums/topics/822141 )
12-10-2018
- Metadata section of general RC rewritten. Content is mostly the same, but wording is more understandable. ( https://osu.ppy.sh/community/forums/topics/763785 )