Hi everyone, I have started mapping a while ago (2 months to be precise) and already had a bit of modding.

As expected from a new mapper, my first few trials were messy (unaware of the ranking criteria, wrong spacing, unefficient use of the mapping tool, whatever you might expect from a starter, and so on). A lot of feedback guided me to watch videos of pishifat: Very useful indeed, lots of subjects and guidelines to get started of mapping.

What I didn't find (even after scouring the whole internet) is the essence of a Hard Difficulty map.

I get that Easy/Normal Diff shouldn't be too hard so that new players get to learn how to play (and actually READ IT)
I also get that Insane/Expert Diff help medium/experienced player to take a step further into improving their skill.
This whole thing is what I understand from the Difficulty Ranking Criteria and from the different low-star maps I dissected or at least tried to understand the mapping process

What I don't get is the Hard Diff :
-(From my own experience) Is it a transitional stage more than a stage by itself, players either leaving or pursuing the game at this level of progression ?
-Can it be really be considered a stage by itself, considering players either learned most of the basic patterns (apart from streams) either lack the skill because they skipped/didn't spend enough time on 2-3 stars map ?

I'm not questionning the existence of Hard Diff, nor asking how to map it. There is definitly something to learn about Hard, but from my perspective, it's like I'm blind : I can touch the essence it's essence, but I can't see it allowing me to get the full description/definition of it.

My thanks in advance for your anwsers.

So you're asking whether Hard diffs are a stage of their own, or just a transition from normals to insanes. Honestly, I'd say they're both.

You said it yourself:

Estold wrote:

(apart from streams)

1/4 rhythms are a massive step up in difficulty from Normal diffs. If you didn't alternate from the beginning, learning to use two fingers for some patterns takes work. Even if you did, hitting 1/4 rhythms accurately takes way more control than anything you'll find in a Normal diff, especially when you also have to deal with the kind of 1/2 rhythm density you usually encounter in Hard diffs at the same time.

It's not just about rhythm density, though; Hard diffs challenge aim and reading pretty significantly compared to Normal diffs. In a Hard diff, you usually have to move your cursor twice as fast as in the Normal diff in the same set while also having to aim more varied angles. As for reading, how different timeline gaps are presented changes from pure time-distance equality to simply using different spacing for different gaps. You also start seeing more overlaps, fairly liberal stack usage, and even jumps and slider leniency abuse.

Now, all of these challenges are even more present in Insane diffs: longer and more frequent streams instead of just triples and quints, even higher spacing that rewards snapping instead of flow aim, more variable 1/2 spacing, different rhythms with identical spacing, and so on. Hard diffs are just sort of there to prepare players for these things after they've learned the basics of the game. How difficulty spreads are commonly modded follows this idea: a Hard diff is expected to offer similar challenges as the Insane diff in the set, just toned down a bit.

However, Hard diffs also have some fairly clear upper boundaries that separate them from Insane diffs. They mostly encourage flow aim; spacing that's constantly high enough to reward snapping to each object is generally agreed to belong in Insane diffs. There are definitely Insanes and Extras that support lots of flow aim, but those have other difficulty elements that put them above Hard diffs and/or high enough spacing that the level of control required to hit the notes would be unreasonable for a Hard diff.

As for rhythm, Hard diffs are effectively constrained to chains of 5 or fewer 1/4 circles in a row. The line between a high Hard diff and a low Insane diff gets pretty blurry when you add finger control elements, but as far as pure rhythm density is concerned, the line is fairly clear. Reading challenges are also very limited in Hard diffs, while Insane diffs have a lot of freedom in this area. Thus, while Hard diffs are generally designed to prepare players for higher diffs, they're still a distinct difficulty level in their own right.

Thank you very much, for this very explanatory and concise anwser.
I get a cleaner view on what has to be done. Thanks to last part concerning finger control and chains, it gave me more insights to make the difference between a Hard and Insane.

When I started OSU! 2 years ago, I though to myself that there was a huge gap between Hard and Insane diff for "no reason". It wasn't about cursor speed or bpm capacity, and more about the consistency and being conscious of a full/half/forth beat. And I think it stayed like this inside me until I started to be cautious on how maps are made.

Thanks again for sharing your thoughts