Modern horizons 3 is interesting to me in that three of the major mechanics in the set were once considered failed or problematic mechanics. Kindred was considered a failure almost immediately after lorwyn and was abandoned. It was meant to be a card type and you now have a defunct card type. You used kindred not only in the tarmogoyf deck but also in a different way as an identifier in the eldrazi deck. Energy was awesome flavor wise and was a success but you failed to balance it mechanically and you had to ban several cards and because of that it seems you hesitated to return to this mechanic in standard. Finally devoid was considered a do nothing mechanic that was not popular. You used all three of these mechanics in modern horizons 3 but they are a big success. What has changed? Is it the execution? Is it experience? Why use these mechanics for such a high profile set knowing their history? Does this give hope for other mechanics that were not popular to return

First, energy was quite popular, the highest scoring mechanic in Kaladesh. Yes, a bunch of cards ended up being too strong, but that means a lot of people played with it.Second, Kindred (formerly tribal) wasn’t unpopular. Our issue with it was it led to a slippery slope where we added a lot of words on cards for little effect. Players have asked for its return.Third, devoid was unpopular, but I think we just positioned it wrong. We made it a mechanic that didn’t do anything which upset people. Had we made it a supertype, I don’t think anyone would have blinked at it.So what happened in Modern Horizons III?We brought back energy, a popular mechanic that players have been begging us to bring back for years. We brought back Kindred (renamed), but that’s not a big element of the set. Again, it’s something players have been asking for.We brought back devoid because we were doing Eldrazi, which was much more popular than devoid. I don’t think devoid is why the Eldrazi theme is popular. The Eldrazi are why the Eldrazi theme is popular. Devoid is just a callback, one we need to make the theme work mechanically.

Would Tarmogoyf be considered vanilla because it has no abilities, french vanilla because it's power and toughness are defined in the text of the card (albeit not by an ability), or neither because complexity or any other reason?

To be vanilla you have to have no rules text (not no abilities), so Tarmogoys if not vanilla.To be French vanilla, you have to have no rules text other than keyword abilities, so Tarmogoyf is not French vanilla.

Why is "Nethergoyf" black? "Tarmogoyf" is one of the few iconic green creatures that has supported green for many years, and its successor should have been in green. I don't think it should have been given to black just because it is also possible in black.

Before Modern Horizons III, there were four green Lhurgoyfs and two black ones (plus two red ones, a white one, and a blue one). Green didn’t have the monopoly on Lhurgoyfs. Plus, Modern Horizons III does have a green Lhurgoyf and a Green Lhurgoyf aura that makes Tarmogoyf tokens, so it’s not as if green missed out on all the Lhurgoyf goodness.

Is the "Tarmogoyf token" method the new standard? I.E. if Roxanne, Starfall Savant was one set later, would she make a "Meteorite token" rather than defining it?
Separately, will you be going back to change any of these on old card like her, or Llanowar Mentor?

I think Modern Horizons sets do things other sets don’t do. I don’t know of any errata in this area.

Re:Power CreepI think the root of the issue is that some long time players are sad that multiformat all-stars are being outclassed. Cards like Liliana of the Veil barely see standard play let alone modern or legacy or Tarmogoyf being so relatively weak that a commander making token copies of it feels like a silly novelty more than a terrifying threat. These cards that are very powerful in theory. They haven't been 1 to 1 outclassed but never the less are functionally not relavent in modern/legacy. This is a hard pill for many players to swallow when these cards were titans for nearly a decade.I think calling the argument of calling this shift power creep or not power creep is splitting hairs and maybe there needs to be some new terminology coined.

It’s the nature of a game that keeps releasing new content. There are formats like Old School (which only use cards from ‘93, '94, and '95) if you want to play with exclusively older cards.

Un-Rules question: If I'm playing with R&D's Secret Lair, what old stuff counts as "different" card types to grow my Tarmogoyf? Defunct types like interrupt and mana source? Renamed types like summon and tribal? What about "enchant creature" and "poly artifact" - are those unique card types or just janky subtypes?

If you’re using R&D’s Secret Lair, you can count card types that were card types at the time of the card’s printing, things like Interrupt or Mana Source. Note that list is pretty short.

Hey Mark, I heard somewhere the Tarmogoyf has still yet to be printed, so far it's been pre-printed and seen several reprints.Do you think we'll see the set that it's originally printed in someday?

Perhaps one day. : )

Tarmogoyf was preprinted in Future Sight, and ever since it has only been in reprint-only sets. Can I request that we get it’s official first printing?

One day…

Does Tarmogoyf check for battles now?

Not until they exist on a card.

Hi Mark will we see a planeswalker with Tarmogoyf loyalty( its loyalty is equal to the number of card types among cards in all graveyards plus 1) this year?

It’s in Streets of New Capenna. It’s also secretly Jace.