Judges exist to provide customer service for all the players in a tournament (contrary to each player in a tournament, which is the organizer's role) by maintaining the integrity of the event. As an effort at preventative action, we have compiled this list of common infractions made at tournaments for players to review. Organizers may wish to use this list (or generate their own) and post at registration.
1. Tokens and Counters – either using non-token cards or same item for two different types of tokens.
2. Conceding with the expectation of being compensated later.
3. Not presenting your sideboard with your deck. Having your sideboard mixed with other cards.
4. Unable to reliably track their own life total.
5. Looking at extra cards - either via PE-Major (e.g. activating a Top that's no longer in play) or shuffling clumsiness.
6. Drawing too many cards at the beginning of the game, especially after a mulligan.
7. Not calling a judge when someone makes a procedural error.
8. Not shuffling an opponent's deck, especially REL 3+.
9. Insufficiently randomizing their deck.
10. Forgetting to check to reset to your main deck before a new match.
11. Returning cards to each player's appropriate deck at the end of a game.
14. Asking your opponent for a ruling. Few opponents will look out for your best interests.
15. Discussion with someone not your opponent or official about the current game-state of any match.
16. Using excessively worn sleeves.
17. Using sleeves that have clearly been pointed out as not allowed.
18. Having some cards in deck (unsleeved) upside down.
19. Using differently worn sleeves for sideboarded cards.
20. No DCI# or Name on decklist.
21. Forgetting lands on decklist.
22. Illegible writing.
23. Overly abbreviated or incorrect card names.
24. Incorrectly filling out played/total columns on limited decklists.
25. Using tally marks/check marks instead of numbers on Limited decklists.
26. Not alphabetizing cards when registering sealed card pool to be passed.
27. Leaving the table/playing area before signing the result slip.
28. Players failing to communicate match result (more common when result slips aren't being used).
29. Not recording unfinished games as a draw on the result sheet.
30. Not verifying results and/or drops before signing (and/or entirely forgetting sign and/or to submit the results).
We will follow this article with a series covering common misperceptions that players have that are the most common causes of disqualifications.