I must say that I am glad you used a real world example of a previous set design as an example in your latest article. My question would be: How do you know if an idea is taking up too much space or is being focused on too hard? Examples: How do you know how many pseudo-Exalted triggers to add to NEO or how much Proliferate to add to WAR?

It’s mostly trial and error. Add some and play. The feedback from the playtest will tell you if the level’s off and usually in which direction.

In terms of the buy abox promos. In my opinion Firesong & sunspeaker alongside The Haunt of Hightower are successes while Nexus of fate was a mistake that should not happen(and the wurm is fine just sees play in one modern deck and thats it). I believe that for future sets the promo will be better suited for janky build around legends rather than spiky competitive cards that people will need 4-ofs, its a great opportunity to make a commander with story relevance that happens to be standard legal

We were trying something new and that requires some trial and error to get right. Nexus of Fate is not where we’re targeting the Buy-a-Box promos.

In my understanding, blue likes science because it's focused on proof, correctness, understanding. It wants to codify information and teach. Red enjoys science, even the learning part, because they enjoy experimenting, practically applications, trial and error. They aren't concerned as much "why" things work, just "if" they work. Red values the excitement of a breakthrough and a finished project, while blue values the contribution made to understanding the world.

Well put.

Is there any particular reason why Sublime Archangel has the two lines: "Exalted" and "Other creatures you control have exalted" as opposed to just "Creatures you control have exalted"? Is there a rules reason or is that just what is decided is the best or easiest to understand way of doing a card with a feature like that?

We’ve learned through trial and error that it’s the easiest way for players to understand it.

I have never seen you accept criticism for a card or design decision. You tend to shrug it off with "some other players like that card" or "I liked the card even if it was unbalanced and we had to ban it soooo I guess it was okay because I liked it." Okay that last one was a little unfair but it is absolutely the vibe you give off. My question is how much, if any, criticism weighs into any of the decisions you make.

I do try to own up to my mistakes. I have written numerous columns about all the different mistakes I’ve made. In “Tales of the Pit” earlier this week, for example, I made fun of my decision to have all the rare creatures in Kamigawa block be legendary which was a horrible mistake. Note though that me making a card that Player A doesn’t like because it was made for Player B is not a mistake. Players not liking something because it doesn’t do exactly what they want it to do is not a mistake. Players disliking a particular choice I made because it’s not the choice they would have made is not a mistake.  A lot of what we do is trial and error and there are plenty of decisions I’ve made that I would do differently. Mistakes, to me at least, are things that when I look back I say “oh, we did it wrong in such a way that the game was less for that decision”. In that regard, I’ve made tons of mistakes. My goal is to learn from them so that I become a better designer. Making mistakes is part of any creative process. Not learning from them is the real problem. That said, I’ll own up to a mistake I believe I made in Dark Ascension. Having looked over all the feedback, it’s clear that I should have figured out how to make a legendary werewolf. It’s something a segment of the audience wants very badly and I believe if we had given the issue enough of a priority, we could have figured out how to do it.