You can set subcategories to be misc. categories, but as far as I know you can't have multiple dropdown menus, I might be wrong though.
When die% was added as an april fools day joke, the set seed category was maximized after one day, by fall damage. The random seed category is the only thing that has any hope of not being maxed instantly, but eventually somebody will get a perfect seed, and the fun will be over. I'm pretty sure most people who suggest die% just want a free world record. There are two leaderboards for die%, (a google sheet made after april fools, and a leaderboard on findseed) and nobody runs it.
Minecraft has it's own forums. Nobody here will know the answer to your question, but over there, people can help you. https://www.speedrun.com/mc/forum
the choco mountain thing is absolutely not the hardest one. abney's consistency at the 1/3 trick is 1/24, and several people have done 3/3 before, including abney, who has gotten it 3 times.
There are a million different glitches in thousands of games, so it's impossible to compare difficulty. Things like carpetless, l4-2, etc. are probably at the top of the list though.
As far as tricks done in runs, Early EC in r2 might be one of the most difficult. Normally in rayman, you have to beat every level in order, with no warps to skip levels. However, there is a part of the game where you can backtrack to a normally inaccessible part of the second level to collect the remaining lums (required collectibles) of the level. However, you can use a very precise glitch to access that part of the level and then skip all the way to a later level (echoing caves, which is why it's called early ec). This trick involves performing an inconsistent out of bounds clip, and then hovering to land behind a loading zone that triggers a cutscene. Then, you have to jump against a wall and get the maximum possible jump height (pretty much random) to clear the wall and get out of bounds again. If you time your hover perfectly, you can barely make it back inbounds and get to the checkpoint and skip to the echoing caves level early. World record runs have to get this trick first try. This works on every version of the game (I think) and is much, much harder than it looks (and it looks pretty hard).
there already is a category for that, on the main leaderboards https://www.speedrun.com/gbt#Boxes the 5box category
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Hello, and welcome to the site!! If you need help with streaming, there's a thread for that. https://www.speedrun.com/streaming_recording_equipment/thread/qlnmy If you want some good games to run, you can check out the roblox series and run any games on that list that look interesting. However, it doesn't need to have a leaderboard for you to run it. You can speedrun any game that you like.
I'm not a fan of advertising games, but here's a game jam game from 2014 called Tim_ https://www.construct.net/fr/free-online-games/tim-109/play It got 2nd place. It currently doesn't have a leaderboard, but an any% run would fit in the short time window you've mentioned and a 100% run would take less than 10 minutes with some practice. There's some RNG, but nothing that heavily affects the speedrun. It's a pretty fun and difficult game to play casually I think, because I played this game the first time over 6 years ago.
Edit: I should probably describe the game a bit too. It's a platforming metroidvania game where you have to collect potions to unlock abilities to progress. You play as a bunny in a world of alligators (or crocodiles, idk) which kill you, shoot lasers, can fly, etc. At the end of the game, there's a final boss, which can be almost completely skipped very easily.
I have a time of 3:04 I think on my yt, but a much lower time is possible if I did more attempts.
The game only has one exploit/glitch that I know of, and it can be used to save a bit of time in 100%, and a bit of time in any%. It's not very hard to do, and it isn't used frequently in the run. The game does have heavy death abuse though, dying to warp to checkpoints and stuff, so if you don't like that kind of stuff I wouldn't run it.
You did not set the date, so it looked as if you simply submitted a bunch of runs that were not pbs. After checking the upload dates of the videos, he verified them. If OP was mistreating you, this isn't the thread to complain about it.