Yes, there are levels that aren't completable as Viridian.

Nazario92's run is timed with in-game time also btw, in case you missed it sillypears.

Doesn't count the time for the run with EB Goes with in-game time Goes to mega satan

What a disaster...

I just think it makes the run diverse by forcing the player to pick up different good items in the runs instead of just the same.

Suggestions (Not well worded)

I think things like cards and pills should be: You may only use Emperor card(for example) in one of the chars, but within that char run, you may use it any number of times you want?

Also trinkets and transformations should be limited to one char run?

I have thought of almost exactly the same idea before, even the part with not picking up the same item twice. However I feel like that rule should be something like: You may only pick up the same itemroom, devilroom or angelroom item once in the run, so that you still can pick up the same HPups from the bossroom.

I have also considered a 26Char Seeded Speedrun where you have to beat both chest and dark room with all characters if the 13Char ever gets too short.

I will at some point run one of these categories whether it's on the leaderboards or not, I just haven't had time to search for seads.