What the heck is an .rmf?
RMF files are basically just midis, but you can embed a soundbank in the file itself. I think this would be great to have as a format, allowing for the creation of midis with custom sounds, very good for creativity and bitpacking!

Tools for rmf midis that could be used
I've found it hard to find tools on .rmf export and playback, but I do know at least 2. A convenient web midi player called SpessaSynth

can easily be used to export .rmf files, you can even embed a soundfont in the .rmf, it is quite easy to do. Spessa can also be used to playback .rmf files. The only other piece of software I know of for playback is Falcosoft's midi player, which plays .rmf files with soundbanks.

Workflow
The process for making a .rmf would be similar to however you do other midi formats. Simply make a midi in the software of your choice, and have a midi out to software that can play back whatever soundbank/soundfont you would be using. After the midi is done, you would convert it to a .rmf with the embedded soundfont in SpessaSynth.

Conclusion
I think this would be a nice way to have midis with soundfonts on BotB, there are only some things about this request that may have particular issues, such as lack of a variety of tools. I think if it is too complicated to have just .rmf submissions, the format could be allowed to have .zip submissions with a midi and a soundfont, or just a midi for battles with a soundfont/soundbank file as a bitpack, as many files with duplicate soundbanks could be inefficient for the BotB server. In that outcome, I guess the format would be midi deluxe or midi+ rather than rmf.

Feel free to discuss about this potential format, fellow battlers!

it's cool that there's a contemporary web tool for this! I hope it's possible to use offline too like jummbox and moai.

there was a related format request a few years ago: "beatnik/rmf", which was focused on rmf as a midi vehicle for old phone soundbanks, but it's potentially as wide as you describe.

I don't have much of an inkling as to what the proper bounds of a format like this would be - it was an open question when I was digging thru format suggestions for Oops! All New Formats last year too - but my gut tells me .rmf is preferable over .zip if possible. a soundbank could be a bitpack theoretically; or otherwise embedded in the .rmf right? max filesize could be relevant here too... soundfonts, especially GM ones, run the whole gamut of size.

I had a thought about "oh no, including soundfonts could involve uploading copyrighted samples with the entry!" but then I also had an additional thought about the whole website. it's obviously something we want to keep to a minimum - nobody wants to put the site or puke7 in jeopardy. but we have so many sample pack formats and there's such a deep sampling culture in oldschool tracking. 🤷 I don't think I could make a convincing argument for drawing the line here in particular.

seems to be a whole bunch of outdated and contradictory info about "beatnik RMF", "RMID" (which originally had the .rmi extension, not .rmf, and whether the purpose of said RMID was to add a useless wrapper around the midi file (which was the case originally) or to add arbitrary extra stuff to the midi file, e.g. https://web.archive.org/web/20110610135604/http://www.midi.org/about-midi/rp29spec(rmid).pdf

i think RIFF/MIDI are so abstract you need a "something that can play midi + samples(sf2/dls/etc)" format not a "file spec" format here

i think midi + soundbank is a great idea for a format but riff midi seems like maybe not the best packaging of that idea, considering how widespread midi + sf2 support is and how narrow .rmi support seems to be. maybe embedding them in a riff file instead of an archive would make playback slightly more convenient but it would probably make most other things less convenient

MIDI+ makes its fifth attempt

Without any research at all, this feels like a slightly more compelling version than my 2017 proposal, but re: jangler sf2 comment I wonder what the most convenient way to do that would be, since sf2 is such an easy thing to create... I think.

This also reminds me of trying to make Nokia Composer or whatever a format the same year but idk if we ever found a way to even revive that software.

i do want to add that, should this become a format (if, not when...) i do think with this community there would probably be folks trying to make the format more accessible in terms of players, toolage and whatnot, it's happened with a lot of other formats on this site before (and iirc panda was even bespoke made to have an ohc friendly format however long ago that was, so...)

rmf sounds like the midi equivalent to s3xmodit and i'd be really intrigued to try and mess around with it, as i previously thought it was just a slightly different and way less popular variant of midi, but obv not from reading this, and it'd also solve the midi+ issue where the playback form was very inconsistent...

...although, yea the argument for inconsistency even here is a very real one. i feel like it might be the same argument for sf2 plus midi though? or esp dls plus midi if this is closer to that. but, if theyre just like, should the samples be interpolated or not or small stuff like that, then we can leave that up per entry i think like we do with s3xmodit and mod*k formats

if this is widely supported by like fluidsynth for example it's cool but if not it makes more sense to just do the "zip file with a .mid in the root dir and a .sf2 or collection of .sfz alongside it" approach and make the tooling for it like we may have to do for rmf anyway

https://github.com/FluidSynth/fluidsynth/issues/1356