I said I was going to compare Modern to other formats, but actually setting out to do that, I'm a bit stuck. The obvious starting point, the format that has the most in common with Modern, really seems to be a stark departure philosophically. That'd be Legacy. They are the two official formats with very large card pools that do not include any restricted cards. And based on that description, Modern and Legacy are much closer to each other than either of them is to any other format. Well, there's a case for that, anyway. One might argue that Legacy is closer to Vintage than to Modern. Depends on how the presence of restricted cards gets weighed. Certainly, there is some overlap between Legacy and Vintage, but Legacy decks and Vintage decks don't really look very much like each other or behave in the same way. Whatever. Although the Legacy card pool is much bigger than the Modern card pool, the relative difference continues to shrink over time, excepting occasional hiccups like True-Name Nemesis or Leovold, Emissary of Trest. The relevant circumstance that this progression doesn't account for is that WotC had already shifted card design away from certain things that didn't make it into Modern, and they have managed never to go back. I've already gone over some of this, so without trying to list them all, I think it's sufficient to state that major, format-shaping cards in Legacy are absent from the Modern card pool and, presumably, always will be. While a dry analysis presenting the difference as Legacy allowing old cards, cards from non-Standard sets, and banning different cards could be useful, I do think there's more to it and that pointing out the philosophical difference could be important. Earlier, I quote this bit... That's telling. Daze is legal in Legacy because it is a Magic card and it was printed. They didn't ban it, so it's available. There was never any discussion in Legacy that cards should or shouldn't be in certain products because it might affect the format. Rather, the format was left to its own devices. And this has been a matter of some controversy, most prominently with True-Name Nemesis, because the "protection from you" ability is so overtly ludicrous. In terms of tournament success, the card's performance has fluctuated over the years, and it has never really been dominant or needed to be banned, although it may have come close (kind of like Survival of the Fittest; yes, I went there). But the very nature of that ability has been seen as something so blatantly out-of-place, so wrong for the game, that it became a matter of controversy independent of the card's track record. And I can see why. But TNN wasn't designed with Legacy in mind. It was built for Commander, a multiplayer environment. In contrast, Modern is curated. We are told that a card might get "vetoed" if it doesn't fit.