Changing exert to stun counters would be a large change since it stops working with untap effects and being able to use those, such as Vizier of Tumbling Sands, is an intended feature of the mechanic. Same is true of persist/undying using finality. It is a feature, not a bug, that you can sac a persist/undying creature twice, reanimate it, then do it twice more. Also, changing old effects to use scry or surveil was largely a buff and these changes would be nerfs which generally upsets players.

Fine points.

Are abilities like Undying, Persist and others with effects like "when this creature dies, return it to the battlefield" possible on the back side of DFCs? And if so, which side would the card be returned on? BTW, Drive to Work is the best! It makes me feel like I've got a pal commuting with me every day. Thank you for letting us listeners hitchike with you on your way to work! :)

Without the card stating otherwise, it would return to the battlefield on the front face. Glad you enjoy the podcast.

Where's persist on the storm scale? It seems to me that would be a very hard card to mechanic to put into standard because +1/+1 counters are such a common theme. For example, Tribute to the World Tree is in standard right now and could easily be part of a combo with many persist creatures.

Persist needing -1/-1 counters makes it return, at least in a premier set, less likely, but not impossible. I’ll call it a 7.

Outside of Modern Horizons, what is the most likely product for persist (or -1/-1s at all) to make an appearance?

A Commander deck.

I love "Persist" from MH2! It makes me imagine a cool super cycle of cards based on Keywords. Can a I get an If or a When the possibility?

If on a cycle, but when on more individual cards, most likely in future Modern Horizons sets.

Which do you prefer: Persist or Undying?

Persist is the better mechanic, but harder to reuse as R&D is soured on environments with -1/-1 counters.

Re: cancellation of +1/+1 and -1/-1 counters, I think the question is more whether you would let a black bordered card play directly with this interaction. Something like a creature with Outlast and Persist. This is a commonly requested type of mix-and-match card that you guys seem to have intentionally avoided. Can I ask if or when?

If. The problem with a set that heavily used both is that it would be very hard to tell board state. At bare minimum, it would require punch out counters to mark them.

Mark, was there ever any consideration to giving the "You can play any number of " cards like Persistent Petitioners, Relentless Rats, and Dragon's Approach the Basic supertype, then expanding the rule that lets you play any number of copies of a Basic Land in your deck to include any card with the Basic supertype? It would allow you to save a line of rules text for these kinds of cards.

But it causes different issues. Basic means other things than “you can play more than four”.

Yesterday was my birthday! Can I get some trivia about my favorite set, Dark Ascension?

I’ve led forty something sets and the only small winter set I ever led was Dark Ascension. I did it because I want Ken Nagle to lead his first large set and a return to a known world (Ravnica) seemed like the right spot. My favorite design story from the set was I was trying to find a cool monster mechanic and was talking with my wife about it, venting my frustration. I really wanted to use persist because monsters have a whole trope of coming back after you think they’re dead, but the set used +1/+1 counters instead of -1/-1 counters. My wife said, “Why can’t you use +1/+1 counters?” And I’m like, “I can!” and undying was born.Happy Birthday!

Are rat/persistent petitioners effects specific to black/blue in the color pie, or is it primarily/exclusively a flavor decision?

Any color is allowed access to “you may have as many copies of this in a deck”.