At least to me, Generous Gift feels less natural than Beast Within. Targeted land destruction may not be a break in white in the sense that it doesn't undercut a core white weakness, but green killing creatures directly has more precedent even if it's considered a break in the modern colour pie; nor is gifting creatures very white. The flavour, fun as it is, of white getting land destruction because an elephant squashes it flat seems a case of stretching flavour to justify an off-colour ability.

Green was never supposed to be able to kill creatures in the color pie. I had a drag out fight over Dessert Twister in Fifth Edition twenty plus years ago (which I lost because there wasn’t a good replacement, but they claimed wasn’t a precedent). And white giving people things in exchange for destroying something has been in White’s color pie since the beginning. So yes, Generous Gift is and has always been more in color pie than it’s green version .

Is it possible to make an extra large set, double in size, to have all 10 guilds in one set?

We experimented with a four hundred plus set in Fifth Edition. It was just too large.

Two quick questions: does rare business gone work on mythics, cards that lost their rare status in iconic master? And if not can I get a maybe on mythic begone?

Rare-Be-Gone destroys all rares and mythic rares. As with all silver bordered cards, qualities of cards are defined by the attributes of that particular card. For instance, Wyluli Wolf has been printed both at common (Arabian Nights) and at rare (Fifth Edition). If both were on the battlefield and you cast Rate-Be-Gone, the rare Fifth Edition version would be destroyed while the common Arabian Nights version wouldn’t be destroyed.

Is it correct that once HOU becomes standard legal, it will be the most cards legal in standard since, something like, 1996? There will be 8 legal sets, ~1740 cards (not counting planewalker deck cards and counting DFCs once.) The eventual new 2.0 standard will be about the same size (6 big and a core set, 249 cards each = 1743 cards) when Standard is at its biggest. New standard is now bigger, no?

That’s not even close to the largest number of cards in Standard. Large sets used to be bigger and core sets sometimes bigger than that (Fifth Edition had 449 cards in it). I think the largest, of relatively recent time, is original Ravnica block and Time Spiral blocks were in Standard together. Cold Snap was included along with the core set and a whole slew of time shifted cards.

Hey Mark. It was my birthday on the 26th and I was wondering if I could get some trivia on my favourite card of all time, Balance.

One of the great Magic mysteries was how Balance got into Fourth Edition. (Note this was before I got into R&D.) R&D knew the card was a problem, it was restricted! My guess is it was a pet favorite of one of the designers and he talked the others into including it. It’s how Necropotence ended up in Fifth Edition. Happy Belated Birthday!

What are the chances of you guys printing a set with more cards than 5th edition?

Low. Fifth Edition had 429 cards. And that’s not even counting the basic lands!

What is Build Your Own Standard?

It was a format I made for a Magic Invitational. You could choose any two blocks and any core set from Fifth Edition forward. Any card banned in Legacy or Block Constructed is banned.

I see most sets have in the range of 250-300 cards. Has there ever been an even larger set than that? And why don't we see like really large sets, like 400 cards?

Fifth Edition had over 500 cards. The reason you don’t see sets that large is we don’t have the resources to make sets that big, not with the number of cards we already generate each year. It also would be a waste as there comes a point where sets are so big that prevent the consistency we want for limited play. They also become very hard for players to acquire all the cards.

So if Beast Within is a problem, what about Desert Twister? Or does that fall entirely outside the bounds of what would be printed in green these days?

I fought very, very hard to keep Desert Twister out of Fifth Edition. I obviously lost. I dislike it as much as Hornet Sting. 

Do you think we would ever see a massive set, like double the size of a large one?

Fifth Edition was almost that large. As we have limits for how many cards we want in Standard, it would be very hard to do.