That's why I said, "I guess trivia is supposed to be obscure and all." I don't think there's a hard and fast rule on this stuff. But at some point, you drift from "tricky questions most people can't answer, but interesting" and more toward "gotcha!" I guess my take is that this quiz has a bit of both. I wracked my brain trying to remember which Future Sight card got reprinted first. I was able to quickly narrow it down to two of the options because I recognized the names as being names used in Lorwyn/Shadowmoor, but then I got stuck (guessed randomly and got it right). I lit up when I saw the one about Squee's Toy because I used to use that card in my casual decks so long ago, but then I suddenly blanked on the set it was part of (I remembered after a few seconds, though). But then I missed the ones about how many languages the game is printed in and felt like that was a pretty fair question to have and that it was on me for not remembering it.
But the thing about the original artwork for "Maro"? I got it right away because this is like the 5-billionth article in which Mark Rosewater has mentioned that information, but it has nothing to do with the game itself. Of course he finds it cool because he designed the card himself, it got named after him, the artwork had an an unusual anecdote behind it and he was able to purchase the original painting. That's fine, but it's just not Magic trivia. It'd be like, "What did I, Mark Rosewater (head designer of Magic) have for breakfast this morning?"
Really, I kind of think that almost all of the ones I missed are good trivia questions. It's some of the ones I easily got but that are staple "Mark Rosewater always mentions this in his articles" that feel like they don't belong. Minor gripe though. Still some cool information in there. I definitely found the bit about Birds of Paradise and Tropical Island fascinating the first time I saw him mention it. It's just that I've seriously seen him bring it up dozens of times, while almost no one else has provided the information. I guess that the nit I'm picking at here is that Magic trivia should draw on things that players can get from multiple sources, and this quiz was more "Have you been paying attention to Mark Rosewater's columns over the years"? Who else has ever told the general public about the art from Unglued 2 being used on Atogatog? That was another one I knew right away. It's in Mark Rosewater's columns/podcasts/social media. And pretty much nowhere else. That's the flaw though: if you follow Mark Rosewater's publications, some of these are extremely easy, and if you don't follow them, you're completely in the dark. I do not think that kind of thing makes for good quiz questions because instead of being a real challenge, it's all or nothing.
All that being said, I do fee like I'm being hard on this quiz. It's all in good fun anyway and it's not like anything is really on the line. It could have been better formatted as a series of "Did you know..." type bullet points instead of a multiple choice quiz, but that's quibbling...