The information provided in the Magic the Gathering Tournament Rules, which you can download here here, only gives us a small amount of information about what misprints are playable. Here are some excerpts from section 3.3 'Authorized Cards' that are relevant:
"Players may use any Authorized Game Cards from Magic: The Gathering expansions, core sets, special sets, supplements, and promotional printings. Authorized Game Cards are cards that, unaltered, meet the following conditions:
The card is genuine and published by Wizards of the Coast
The card has a standard Magic back, is a double-faced card, or is a card that is part of a meld pair.
The card does not have squared corners.
The card has black or white borders.
The card is not a token card.
The card is not damaged or modified in a way that might make it marked.
The card is otherwise legal for the tournament as defined by the format"
"Players may use otherwise-legal non-English and/or misprinted cards provided they are not using them to create an advantage by using misleading text or pictures."
"The Head Judge is the final authority on acceptable cards for a tournament."
There are a few types of misprints that we can rule out after reading that, or can we? I don't know about you, but those rules raise a lot of questions for me. The one clear thing is that the head judge is the final approving authority, so if you plan to play with misprints, you're better off confirming it with the HJ before you start any tournaments. Since I had a few questions, I decided to ask a local LvL 2 Judge:
"The card has black or white borders" At first glance miscut cards would seem to violate this rule. I know of borderless altered cards that wouldn't pass a deck check. Do miscuts potentially have the same possibility of failure? Also here are some misprinted cards with errors on the borders, same question for these.
This rule is specifically referring to gold border cards or the grey bordered cards from the UN sets. It's less about what the cards look like, and more about where they came from. With that being said, as long as they pass normal deck checking and marked card standards, they should be fine to play.
"The card is genuine and published by Wizards of the Coast" How would you see NFC cards falling into this ruling? Would most head judges allow NFC or disqualify them based on this rule?
This one is tricky because while a lot of judges know about the existence of NFC cards, properly identifying them is really difficult. Personally if I knew a card was NFC I would not allow it, but I know many judges who are much more lenient towards them.
"The card has a standard Magic back, is a double-faced card, or is a card that is part of a meld pair." This rule would appear to effect any type of misprint specifically relating to the back of a card. Ink errors, miscut backs, etc. Can we assume that these types of errors are ok to play if we use opaque sleeves?
This rule is mostly likely referring to cards like the World Championship edition decks where the cards have a completely different back. I would treat any card with a standard, but misprinted back, whether it be miscut or some other ink error the same as double sided or meld cards. They are ok as long as they're in opaque sleeves and as long as they are not visually distinguishable per normal deck checking standards.
With that being said, in the case of cards with miscut backs, if the back of the card was mostly (50% or greater) something other than the MTG back (see image to the right) such as the white sheet edge, I would not allow it.
"The card is not damaged or modified in a way that might make it marked" Here are some crimped cards that I've double sleeved. Would these be acceptable in competitive REL environment?
Sometimes double sleeving a card can increase the visibility of the top edge and might have the opposite effect of what you were intending. A card with the crimp on the top edge of a card would very likely be visible and thus get flagged as a marked card during a deck check. However if the crimp isn't directly on the top edge (see examples below) these could pass a deck check since they're not visible from the top. Vertical crimps effect the top edge of the card, and would not likely be allowed either.
"The card does not have square corners" Based on the conversation so far, it's safe to assume that this rule isn't referring to misprints, but instead the collectors edition cards released in the past. What are your thoughts?
That's how I'd interpret the rule. However I'd treat a card with a square corner a bit differently than the other cases we've discussed so far. While performing a deck check on a square cornered card, in addition to checking visibility on the top of the sleeve, I'd be sure to check to make sure the card isn't physically distinguishible through physical dexterity as well. Can the square corners be felt while shuffling? Also, decks that are shuffeled frequently usually have sleeve corners like these (see image). I'd want to check to make sure a square cornered card doesn't have a visually different effect on a shuffled sleeve. I'd also think that square corners would require a bit more investigation, and I'd have ask the player several questions.
Can a misprint be allowed in one deck, but not another? As an example, take this forest (see image); One person wants to play it in their mono green elves deck and another wants to use it in their junk (WBG) deck.
I can see some judges allowing that forest in the elves deck, but I don't think any judge would allow it in the junk deck due to how easy it would be to mislead other players with it. While the name "Wald" (German for 'Forest') is clearly printed on the card, the art isn't clear, and can be used to create unfair advantages.
What about this Blessed Orator? Would it be acceptable in a white weenie deck?
While this card has the name and mana cost visible, I would not allow this since the majority of the card is not easily identifiable as Blessed Orator. There's part of the Drudge Skeletons name and casting cost, but since the majority of the card is Drudge Skeletons, I don't think it should be allowed.