A leaderboard has been set up for individual levels! Currently, there are three categories: (1) Normal Mode, (2) 9 Heads and (3) Puzzle Pieces.
For the sake of convenience, I think you should be allowed to submit a Normal Mode run as a 9 Heads run, but not the other way around. For example, having more heads on 1-1 does not make much of a difference.
Please let me know if there is anything else I should add or change.
Sorry for the delay! More categories have been added. お待たせました。より多くのカテゴリが追加されました。
This should have been brought up when the PS4 version released, but with the recent release of the Steam version, and potentially a new surge of interest in the speedrun, now seems like a good time to separate the leaderboards for the original PC version and the PS4/Steam version, the latter two being pretty much identical.
The original Japanese and English-patched PC versions have clear advantages over the more recent versions that were changed in a number of ways. These changes range from re-tuned experience gains, boss health values and boss damage values to equipment pick-ups, all of which affect the speedrun.
Additionally, the original version allows you to skip all start-of-level dialogue by simply playing through the game once and starting a new game without exiting completely, as the game does not reset those particular flags on a new game.
And so, in order to make the two more recent and accessible versions viable to speedrun, I think it's only right to separate the leaderboards for the classic PC version and the modern PS4/Steam version.