Everything you need to know if you’re going to be part of the Deck Check team at your next Constructed Grand Prix in one handy place.

Step 1: The Selection

On Saturday, at the beginning of each round, the scorekeeper will provide a list with random tables, and you or your Team Lead will select which to check. Sometimes we do a targeted deck check, because a suspicion has been brought to our attention: a player may be suspected of Insufficient Shuffling, their sleeves may be feared to be problematic, maybe some foils are easily visible, and we want to verify what’s going on to protect tournament integrity.

On Sunday, we use a brilliant piece of software to help us select specific tables so we’ve checked all players that make Top 8 before Top 8 starts. We have had some unpleasant surprises in the past where a decklist error or a deck/decklist mismatch was discovered only during the Top 8, or even during the finals. Not only does this look horrible on camera, it also implies that a player may have been playing with an illegal deck all weekend long, and a Game Loss in the Top 8 has more severe consequences than during an earlier stage of the event. So we would rather discover any issues before the Top 8 starts.

To perform a deck check, we obviously need a decklist to compare the deck with; because lists can be submitted online, on paper at the start of the event, or on paper the day before if the player has byes, we use an Excel sheet to keep track of where lists can be found. Long ago we did everything on paper and spent hours sorting lists, but now we use modern technology to make our lives so much easier. Make sure to ask your Team Lead to explain to you how to find, store, and return lists, to not mess up this delicate system.

Step 2: The Setup

At events of this size, we have the luxury to work together with a lot of colleagues, so let’s make good use of this opportunity. Often, deck checks are done in couples: one partner goes out on the floor to swoop the decks, the other stays in the deck check area to collect the decklists.

While your partner is fetching the decks, you have time to count the lists and verify that you can read all card names. Look for unusual or truncated names that could be ambiguous. Before you have seen the decks, do you have any doubt which 75 cards will be handed to you?

When you’re on the lookout for swooping decks, others may need you. If a judge asks you for help, for example to help distributing result slips or for double-checking a ruling, tell them you’re currently unavailable due to team obligations (they will understand what you mean without alarming all players around you). Sometimes, you have to prioritise helping another judge over doing the swoop, but this is rare. It may happen if a judge needs you for approving a back-up or HCE and there are no other L3s available at all.

If players call a judge, try to see if another judge is closeby who could take the call for you. Don’t be shy to directly ask another judge to take the call, even if you’re closer by the table where the call is. But if no other judge is available, please help these players: maybe the call is very short and you can still do your deck check, but letting players wait while you are close by while you appear to be available is very poor customer service. Worst case scenario, the target table already drew their opening hands or even started playing, and you have to select a random other table this round for checking; it’s unfortunate, but not the end of the world.

If you can’t afford to miss this specific table, perhaps because it’s a targeted check, try to inform another judge about your plans so they can shield you and take calls for you. If you’re done fetching and checking the lists, try to go out on the floor close to your partner, so you may help or shield them if needed. It’s never a good idea to collect decks after opening hands have been drawn or even after the game has started, unless directly instructed to do so.

Step 3: The Swoop

There are different ways to do a swoop. Some judges advocate being as invisible as possible to completely surprise the players you’re going to check. I have a different preference: try to give at least 6 tables the impression you’re going to perform a deck check at their table by being very clearly visible and present, looking at several tables at the same time, maybe even leaning in a bit more than you would do when “just” watching a game. After all, our real goal is not catching clerical errors but deterring cheaters. More cheats happen with shuffling than with, ehm, things we could detect by doing a deck check, so watch closely as your target table shuffles.

When collecting the decks, make some noise: announce loudly that you’re doing a deck check. In case anyone closeby missed you, make sure that now they know we’re doing deck checks and they really shouldn’t try anything funny. Even if we only do a few checks in reality, players should leave the GP with the perception that we did a lot of checks and they have a very real chance every round to get deck checked.

Oh, and in case someone did do something funny… make sure they don’t destroy the evidence. If they pre-boarded against this opponent, do not let them “accidentally” drop their deck and sideboard on the floor. If they have 2 sideboards, or a 20-card sideboard, ensure they hand you all the cards in their deck box, not the 15 cards they registered. That’s why I prefer to grab the decks from the table myself, one in each hand. Then I put the decks on top of their deck boxes and grab those as well. If they have a result slip already, don’t forget to bring that one to the deck check area, especially during mid-rounds. Look at the clock or start your stopwatch.

Step 4: The Actual Check

Open the deck box and verify its contents. Are there a maximum of 15 sideboard cards, and are they all on the list? Now, put the cards from the box on top of the deck and check all 75 sleeves for markings. Can you easily identify some cards, for example because the maindeck sleeves are severely more worn than the sideboard cards? Now, remove the sideboard cards and put them back in the box, to avoid mixing them up with the maindeck.

What we don’t do now: look through the deck to see if there’s a pattern. Human beings are terrible at determining true randomness, and even perfect shuffling can lead to some pattern. We don’t want the deck to be random. We want the deck to be properly randomised. That’s why we don’t perform statistical analyses (although they are really cool and interesting!), but we look at how the player shuffles. And remember, we already did that. So let’s not waste time here and let’s avoid false accusations. Unless you have a specific reason to be suspicious based on what you saw while they were shuffling.

Do the drop test: drop the deck from 10 centimeters (4 inches) height and see where it splits. Shuffle, repeat. Do you frequently get the same card, maybe because it’s a foil or an altered card? Are the marked cards of the same kind, for example all creatures or combo pieces? If so, there may be grounds for a Marked Cards penalty, and it may even have to be upgraded to a Game Loss. Think of how you would rule this at your local PPTQ, then get your Team Lead involved and propose to them your remedy.

Step 5: The Boring Part

Now you sort the deck and check it against the list. Usually, this is the least interesting part, but at Day 2 of a GP, it definitely is important: we don’t want coverage to publish different Top 8 lists than the players actually played. If we find a problem here, it’s going to be a clerical error, and not a cheat. But what we do here is customer service for more than 10.000 people at home, so let’s do it carefully and consciously!

There is no best or easiest way to check a deck against a list. Every deck and every list is different, and every judge has different preferences. Experiment and do what works best for you. I like trying to sort the cards in the same way the list is ordered, as it makes it easier to match. Sometimes, I prefer sorting the cards by mana cost and/or colour. Rarely do I sort out cards in individual piles by unique name.

If it’s a post-board game, I like to put coloured dots on the decklist to indicate which SB cards are in the MD and vice versa: while checking the SB, I put a red dot next to SB cards that are not in the SB anymore and I put a green dot next to MD cards that I encountered in the SB. If there are multiple copies, I put as many dots as there are cards. This makes checking the post-board MD as easy as a pre-board MD. So make sure to always have two non-black colours of pens on hand, as they also help you to more easily organise your feedback for multiple judges!

After you’ve checked all cards, pile them up in the same order as the decklist is written. Then check the sleeves for a pattern again. I like to hand back the deck ordered, to prove to the players that we actually did a deck check. For safety reasons, on the way back to the players, I prefer to insert the decks into the deck boxes.

As a kind reminder: on Day 1, we have a strict limit of 7 minutes for performing a deck check, as we want to avoid time extension of more than 10 minutes. If after 7 minutes you haven’t found a major issue, the deck check is over. That’s why we start with checking the most important elements and finish with the boring part! However, this doesn’t hold true anymore on Sunday. Coverage needs to know for sure that the Top 8 decklists are correct. Try to finish within 7 minutes, but take more time if you need it.

Step 6: The Debrief

Thank the players for their patience, instruct them to once again check their sideboard, explain they get the time you took away from them plus 3 additional minutes for checking and shuffling, be generous with the time extension you give, and don’t forget to enter it in Purple Fox.
What I will not do is tell the players that everything was in order or that we found no problems: I don’t want the burden of such expressions on my shoulders. Imagine they get deck checked again next round and they receive a penalty for some problem… and you said just an hour before that there was no problem at all. Let’s avoid that feel bad moment if we can. But this is a semantic detail and not the most important thing.

Stick around the table for 30 seconds; players may have a question for you, and we want to be there to answer it. Take as much attention and patience for the debrief as for every other step: it’s here that we interact with the players, it’s right now that we deliver customer service and make a lasting impression… so give them your best smile!

Step 7: The Clean-Up

Leave the deck check area ready for the next check, return all lists to the correct place, report any interesting findings to your Team Lead. And then prepare either for the next deck check or return to the floor to provide floor coverage and help players and your fellow judges.

Thanks for reading, greetz,

Dustin.