Shuffling is a critical aspect of Magic: the Gathering (MTG), ensuring fairness and randomness in gameplay. However, certain shuffling habits can negatively impact the game, whether by causing wear and tear on cards or by introducing unintentional biases. I myself try to shuffle as much as possible in order to randomize my card draws but unusually I will save time by riffle shuffling less.

Here are the top shuffling habits that Magic: the Gathering players should avoid:

1. Insufficient Shuffling

• Problem: Leads to predictable draws and uneven randomness.
• Avoid by: Performing at least seven riffle shuffles or a combination of different shuffling techniques to ensure true randomness.

2. Pile Shuffling as the Primary Method

• Problem: Does not randomize the deck; it merely organizes it into specific sequences.
• Avoid by: Using pile shuffling for counting purposes only, followed by thorough riffle or mash shuffling.

3. Overhand Shuffling Exclusively

• Problem: Fails to sufficiently randomize the deck due to its gentle nature.
• Avoid by: Incorporating riffle or mash shuffling into the routine to achieve better randomization.

4. Inadequate Side Shuffling

• Problem: Can result in clusters of similar cards, impacting game fairness.
• Avoid by: Ensuring side shuffling is thorough and supplemented with other techniques.

5. Not Shuffling After Sideboarding

• Problem: Cards may remain clumped together, revealing potential strategies to the opponent.
• Avoid by: Always shuffle your deck thoroughly after sideboarding to maintain randomness.

6. Shuffling in a Predictable Pattern

• Problem: Reduces randomness if the shuffling pattern is consistent and predictable.
• Avoid by: Varying the shuffling methods and patterns to prevent predictability.

7. Improper Shuffling Technique

• Problem: Can damage cards, especially valuable ones.
• Avoid by: Using gentle yet effective techniques like the mash shuffle and avoiding excessive force.

8. Relying Solely on Opponent’s Shuffling

• Problem: Places trust entirely on the opponent’s shuffling habits, which may be insufficient.
• Avoid by: Always offering to shuffle or cut your opponent’s deck to ensure fairness.

9. Shuffling Too Quickly

• Problem: Increases the risk of accidental reveals or damaging cards.
• Avoid by: Taking time to shuffle properly without rushing, ensuring cards are not exposed or damaged.

10. Inconsistent Shuffling Routine

• Problem: Can lead to uneven randomization and potential patterns.
• Avoid by: Establishing a consistent shuffling routine that combines multiple techniques for optimal randomization.

I have found this post from Ask the Judges Tumblr account regarding the reasons why pile shuffling your deck is not the best practice to randomize the cards. I myself do this shuffle ritual on every game of my matches, from FNM to big events like a Grand Prix. The author describes that the issue that results from this practice calls for slow play and cheating.

Quoting from the article, here are the reasons why:

There are generally three reasons people give for pile shuffling:
1. To prevent “clumping,” meaning when cards of the same type, generally lands, end up in long sequences after shuffling, resulting in a game loss due to mana flood or screw.

2. To prevent “clumping,” meaning when sleeved cards physically stick together, resulting in cards of the same type, generally lands, ending up in long sequences after shuffling, resulting in a game loss due to mana flood or screw.

3. To count the cards in your deck, to avoid a game loss due to preventing an illegal deck.

None of these is a valid reason to pile shuffle. Here’s why:

1. This one is straight cheating. If pile shuffling has any influence on the final configuration of your deck, then you did not sufficiently randomize your deck, in which case you are cheating. A genuinely randomized deck is not the same thing as a well-mixed deck. People generally expect random sequences to have fewer long strings of the same kind of thing than they actually do. If I asked you to go flip a coin 100 times and tell me the result, and you lazily just made up the result, you probably wouldn’t give me a sequence with very many long sequences of consecutive heads or consecutive tails. Such a sequence has about an 80% chance of having a string of 6 or more consecutive heads or tails, though the one you give me probably doesn’t have one. Similarly, If I told you to stack a magic deck in a “random” way, you probably wouldn’t get mana flooded. This is why people who aren’t very diligent about shuffling criticize the shuffling algorithm on Magic Online – they get mana screwed more frequently online than in real life, because Magic Online produces something much more like a random deck configuration than your shuffling does.

2. This one is remarkable to me. If you actually have cards that stick together you need to either a) buy better sleeves; b) buy new sleeves; or c) wash you damn hands. You certainly aren’t using sleeves that are sufficient for play at competitive REL. If you mash shuffle properly and they still stick together, stop gluing your sleeves together.

3. This one is the most defensible, if you haven’t thought it through. As I mentioned before, if you shuffle sufficiently after pile shuffling, then your deck should be truly random, so it seems that there’s no harm in it. The reason it annoys me when people pile shuffle is it takes a goddamn lifetime. Slow play is already rampant in magic, especially in paper. The extra time spent shuffling compounds the problem that a slow opponent will cause a draw in paper, in stead of just timing out on magic online. If you are actually worried about having the wrong number of cards, count your cards the normal way, with them facing you. It’s faster than pile shuffling, and you’re going to do it anyway if you have the wrong number of cards.

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