Can I get a maybe for returning to Ravnica in the next 5 years?

Maybe. : )

'New cards or mechanics. Basically, new Magic mechanical design. Have fun doing it (Magic design is fun), but I can’t see it.' I wouldn't dare try it. It's just clarification for future requests like a Mardu-partner-with vampire pairing or a card called 'Mock Exam' for the upcoming Strixhaven set.

That stuff is fine.

Can the rules handle a DFC that both can be cast on either side AND transforms between them?

The Transformers cards did something like that. The rules need to be tweaked to do both cleanly.

What’s the difference between unsolicited material and hypotheticals like the red-exile draw that were originally asked here before making its way into the game? I’m asking in good faith, playing around with hypotheticals is fun but I don’t want to get you in trouble.

Asking to take an existing thing and swap color or card type is fine.

Hi Mark,Why did it take so long for full-art lands to make a comeback after original zendikar? What changed to make you want to do them for almost every set now?

A change in philosophy in how we wanted to use them.

I've noticed a lot of simic cards that copy enemy permanents recently, but I was curious about how that works pie-wise, since blue copies permanents all on its own while green rarely has that effect for even their own stuff, but it seems to be a pretty big thing for green+blue recently

Green is allowed to copy its own permanents, but it doesn’t do it a lot.

If you did werewolves on a different plane, do you think they’d still be TDFCs, or would you do them different? And if they were TDFCs, do you think their Transformation condition would be the same or different?

I think we’d probably make Werewolves on another plane singled-faced.

Does the popularity of Universes Beyond and Horizons sets raising the bar for supplemental sets make you less likely to try new kinds of supplemental sets?

Yes. That said, I do think we’re exploring new means to get out experimental types of play experiences.

Do marvel characters that can fly but not naturally have flying? For example, storm doesn't fly, she rides air currents. Magneto doesn't fly, he is manipulating metal in the ground to simulate flight. Jean grey doesn't fly, she uses telekinesis. Do these characters have flying or do they have activated flying or something to else to represent this is not true flight

If you can propel yourself through the air through whatever means, you can have flying.

One with Nothing is the strongest card in the game, but it has a huge problem: it can't be pitched to Force of Will! Can we have a version of that effect that costs U/B (hybrid)?

I don’t believe every card needs to be pitched to Force of Will. : )