Q: What's the deal with X spells? Can I play my Genesis Wave, ____ Sun's Zenith?
A: The converted mana cost of a card is the sum of the numbers and mana symbols in the cost. Cards with X in the cost treat X as 0 when determining the converted mana cost of the card. Note that the word "card" is used, since the converted mana cost of an X spell (when the card is on the stack) is determined by what value you have chosen for X, plus all other numbers and mana symbols in the cost of the card.
A (short): count the symbols and numbers, treat X as 0. Did you count to 0, 1, 2, or 3? yes? you can play it.
Q: Split cards, do those work?
A: The comprehensive rules have been worded in such a way as to allow for some split cards to be played. If a split card's individual sections both have a converted mana cost less than 4, it is legal in the format. Split cards are still subject to the colour identity rules- so be sure that both halves are legal in your deck.
A (short): you can play: Far // Away, Turn // Burn, Night // Day, Dead // Gone, Life // Death, Stand // Deliver, Trial // Error, Rise // Fall, Fire // Ice, Give // Take, Hide // Seek, Illusion // Reality, Profit // Loss, Pure // Simple, Ready // Willing, Supply // Demand, Wear // Tear, Toil // Trouble, Wax // Wane
Q: What about Double-Faced or Meld cards?
A: The rules governing Converted mana cost on Double-Faced and Meld cards mean they have the same CMC on the front as on the back- for Meld, if both halves are legal individually, the melded creature is legal.
A (short): If the front is legal, the back is too.
Q: How do the Wish cards work?
A: For Tiny Leaders "outside the game" refers only to the cards contained in your sideboard. (Waiting on a quote from our Rules Manager).
A (short): you can Wish for cards in your sideboard, just like in any Eternal format.
Q: Why no 4 cost generals?
A: The reason we stuck with 3 CMC for the generals is pretty simple- it's a lot of complexity and work, with the distinct possibility of breaking the format. Adding a bunch of rules to say "oh but the general can be 4 CMC, except you can't play these guys, oh and X, but also Y" is needlessly complicated and when introducing a new concept, simplicity is key- the easier it is for someone to understand what you're trying to do, the faster they catch on and the more likely they are to share the concept.
A (short): we didn't want to, it was too complicated for a bunch of reasons.
Q: why is ____ banned / not banned?
A: The ban list is managed on a case by case basis, currently- if a card is brought to our attention, and we haven't had a problem with it yet, it will be tested in the decks designed to use the card to its fullest extent. For power level testing: multiple deck variations will be tested in multiple match ups, with win percentages recorded on a basis of [problem card drawn in opening hand, cast]; [problem card drawn in game, cast]; [problem card drawn, not cast]. With this data and a large volume of testing, we can determine whether a card's power level is too high, increasing win percentage by a large enough factor that it becomes unreasonable to not play the card. For other considerations testing: judges and players are polled about a card's impact on game duration, fun factor, or ability to "play a game of magic", these results are considered and a determination is made- these polls are non-scientific, but we use them to get a pulse on certain cards in the format.
A (short): If it's not banned: it hasn't been a problem yet; there's a direct counter to the card/ archetype; or it's being tested, but it's not banned until we know one way or the other. If a card is banned: it's been a problem we couldn't solve; it's banned for power reasons; or it's format warping, not just game warping.
Q: why 25 life? why not 20? why did you change it from 30?
A: The life total was tested extensively, we originally had it at 30 to fit the theme of threes, but after a long testing period, we determined that 30 life was too much, as even a poorly constructed control deck could stabilize and win from 30. 20 life was considered, and tested lightly, but the aggro decks and burn decks enjoyed a nice 70+% win rate from 20 life. 25 seemed a good middle ground and testing showed that was correct.
A (short): Goldilocks situation- 30 life, control decks win; 20 life, aggro decks win; 25 life? just right.
Q: if a Leader would go to your library, can you put it in the command zone instead?
A: This is a holdover from the French EDH rules (Duel commander), one that we did not take when we made the rules for Tiny Leaders. "Tucking" as it's colloquially called, was deemed early on to be a part of Magic and a good way to combat some of the nastier Leader-centred strategies that some decks employ.
A (short): No.