No idea if this is balanced. Help!

Balance is probably fine, though this effect almost certainly wouldn't be red nor an instant.

It seems red to me, a mix of randomness and land destruction. What makes this not red? Not saying you're wrong, just curious to hear your reasoning.

If I was to guess, I would say that the problem is the ability to target yourself. It cuts a little too close to Scapeshift. The only difference is that the lands are random.

Random is red. But a card that prevented damage to a random creature isn't red... it would probably end up being R/W. This card, as it stands, is probably R/G or maybe R/U.

Also, while I don't agree that this being an instant makes it less red, I will say it doesn't really make sense for the card to be an instant. As far as I'm concerned, if it gets the job done it's supposed to do at sorcery speed, then it should be a sorcery. Everything else is whistles and bells.

I think this is fine in mono-red. I'd make it affect all players though. You could make it RG if you made it anti-non-basic somehow.

I'll second dude's idea. Affecting everybody feels pretty red, too.

Alright, I made it affect all players and a sorcery: Is it still balanced? Is it worded correctly?

I like this version quite a bit. And I like the flavour text, although I think it needs to be removed, its too wordy already :(

I need the flavor text, the challenge this is for requires flavor text. Should it say "all lands" instead of each?

If this is for a challenge that needs flavour text, then you need to remove some rules text. This has too many words on it. Wizards never print flavour text on cards with this much rules text; if you're required to have flavour text then you need less rules text.

"each land" is generally better than "all lands". Either is fine in this case.

Oops, yes, that's hard. The wording is really similar to Warp World, and that's already too wordy for a card despite being fairly simple.

I almost wish there was an ability word for "that X's controller sacrifices it, then reveals cards from the top of their library until they reveal an X card. They put that OTB and the rest on the bottom in any order".

You can make some minor savings. I think "all lands" is better than "each land" here. Leave out "under his or her control", I think that's the default now. "then shuffles the rest into his or her library" is slightly shorter than "on the bottom in any order". But I think that still leaves it too long.

I tried removing all the "each player" and changing all the pronouns to "you" and adding a "then each player does the same" at the end, but it wasn't shorter.

You may have to abandon this idea as much as I like it -- if it doesn't fit, it doesn't matter how good it is. Or maybe something like, "exile all lands, then each player puts X of them OTB at random where X was the number of lands they controlled exiled this way"? That has a similar idea, it will play rather differently.

I feel like it might be "Then each player."

Looking at Warp World, you're right.

That's a much better number of words. I'd suggest removing one or two from the flavour text (maybe "courts of" or "burning") to try to get it down to 2 lines, but that's your call.

If you want to truly optimize the word count at this point, you're probably better doing it in MSE to get it exact.