Open Hand, Closed Hand


School Dominator, Apt

The first lesson, there are no limits to knowledge.

 – School Dominator, Apt

One topic of discussion among Cardfight!! Vanguard blogs is the concept of perfect memory and/or knowledge of an opponent’s resources, especially the opponent’s hand. Since this knowledge would be advantageous to the player, there have been many attempts at trying to apply this in game. One such method that has been discussed is the use of memory of what the opponent drive checks during the attack phase of his or her turn. Such discussion around this topic can be found around the community, such as the article on perfect knowledge from vMundi and the article on perfect memory from TehNACHO. This technical article is meant to implement and apply such theories around the use of memory in a normal game setting.

One such application of this is the use of a strategy of reading resources in hand that looks at open hand and closed hand. Before this can method can be explained, the terms “open hand” and “closed hand” should be defined for clarification. Open hand is the group of the cards in the opponent’s hand that are known to the player. In contrast, closed hand is the group of cards in the opponent’s hand that are not known to the player. Furthermore, cards that are in closed hand will be referred to as closed cards and cards that are in open hand will be referred to as open cards. If one can track the open hand and closed hand of the opponent (along with the rest of his or her field and drop zone), the player could know up to 2/3 of the cards in play on the opponent’s side of the field 1.

So… how does this work? In order to determine this, it is crucial to see how the general concept of open hand and closed hand are seen in game. To conceptualize a game for the sake of demonstration, a series of diagrams will be shown that will depict a turn in game from the beginning of a typical game. Each figure will have a caption depicting the point of game that the picture in the figure represents. In these figures, the turns will go in the normal pattern of play. Each diagram will depict both players’ fields, which will include hand and board. Hand will be depicted by cards on the end of each play mat and will either be face down (representing closed hand) or face up (representing open hand).

Let us consider the beginning of a game. At this point in the game, the only thing that each player has seen are the starting vanguards on both sides of the field. Though this is the case, more information is available to the player in the first few turns of the game.


Figure 1. Beginning of the game, with revealed starting vanguards. Each player has five closed cards in hand.


Figure 2. Player 1 (player with white play mat) has taken his first turn. End phase of player 1’s first turn. Each player has five closed cards in hand.


Figure 3. End of main phase of player 2’s (player with green play mat) turn. Each player has five closed cards in hand.


Figure 4. Beginning of player 2’s attack phase of her first turn. Player 2 is attacking player 1’s vanguard. Drive check has not been initiated at this point. Each player has five closed cards in hand.


As seen in diagrams 1 and 2, nothing of either player 1’s hand or player 2’s has been revealed except for the vanguards that they have promoted in the first phases of game. Though this is the case, this changes when player 2 drive checks, as seen in Figure 5 and 6.


Figure 5. Attack phase of the player 2’s first turn. Player 2 is attacking Player 1’s vanguard. Drive check reveals Ancient Dragon, Gattlingaro. Each player has five closed cards in hand.


Figure 6. Ancient Dragon, Gattlingaro is added to player 2’s hand after the drive check. Player 1 has five closed cards in hand at this point, while player 2 has five closed cards and one open card (as depicted by the face up Gattlingaro in hand).


Drive checking in Vanguard is one of the main methods of finding out what is in your opponent’s hand. Player 1 is now aware that Ancient Dragon, Gattlingaro is in the opponent’s hand. To reiterate, the cards that player 1 does not know in player 2’s hand is closed hand. In the Figure 6, the open hand portion of player 2’s hand is revealed for the sake of demonstration. The remaining diagrams will track player 1’s and player 2’s in the same manner. This demonstrated open hand portion of both players’ hands becomes more prominent as the game goes on. This is demonstrated in the following diagrams.


Figure 7. Stand and draw phase of player 1. Player 1 has six closed cards in hand. Player 2 has five closed cards and one open card in hand.


Figure 8. Attack phase of player 1 with drive check revealing Machining Firefly. Player 1 has five closed cards in hand. Player 2 has 5 closed cards and one open card.


Figure 9. Machining Firefly is placed in hand after the drive check and before player 2 takes two damage, since Firefly’s critical effect and power have been given to player 1’s vanguard. Player 1 has five closed cards and one open card in hand. Player 2 has five closed cards and one open card in hand.


Figure 10. Stand and draw phases of player 2’s turn. Player 1 has five closed cards and one open card in hand. Player 2 has five closed cards and one open card in hand.


Figure 11. Player 2’s ride phase. Each player has five closed cards and one open card in each of their hands.


Figure 12. Player 2’s main phase. Player 2 has called Ancient Dragon, Dinodile to the rearguard from the player’s closed hand. Player 1 has five closed cards and one open card in hand. Player 2 has four closed cards and one open card in hand.


Figure 13. End of player 2’s attack phase. Ancient Dragon, Dinodile has been added to hand after being revealed in player 2’s drive check. Player 1 has five closed cards and one open card in hand. Player 2 has four closed cards and two open cards in hand.


As seen in the diagrams above, one can see that the open hand of each player increases with each drive check. One can also see through observation that the closed portion of hand decreases as each player either places rearguards on the field. This decrease in closed cards in hand also can be caused at any other time they are used out of hand (e.g. guarding with cards in hand).

The application of theory referred to in the introduction of this article is the use of memory to keep track of the opposing player’s open hand. With the information about the opponent’s open hand, the player could have the capacity to make better decisions based on the increased information compared to the player who does not keep track of this kind of information. Though this is the case, memorizing all of this information can be a challenge. After testing this method several times, this author can give a few pointers around this method:

  • Keep practicing. This method takes time to learn, so try to get used to keeping track of hand through the course of your local tournaments and casual play.
  • Improve memory. This is part of the reason that you practice this method of playing Vanguard. The old saying goes that the brain is a muscle. If this is true, then practicing the use of memory in games could prove useful in improving memory. Beyond that point, improving memory will help this method of keeping track of open hands and closed hands become more accurate and more effective in games. One useful article on this subject is available on V-Mundi, and is found here.
  • Track problem cards. An easier way of tracking what is in the opponent’s hand is to keep track of cards that could be a potential threat instead of all potential attackers in hand. These potential threats are those cards that are essential to the mechanics of the opponent’s deck or detrimental to the mechanics of your deck. Examples of such cards are cards like Tidal Assault (which helps Aqua Force achieve multiple attacks) or Grade 3’s (in the case that you are Megacolony and you are thinking about stunning the vanguard).
  • Track perfect guards and 10K shields. On the flip side of the previous point, keeping track of perfect guards and 10K shields allows the player to determine critical times to attack certain units or finish the game. This is especially important for aggressive decks that have big late game plays that can be stopped easily by perfect guards, such as Dark Irregulars (with the exception of Gille de Rais) or Tachikaze.

I hope you enjoyed this article. If you have any questions or comments, please feel free to put them in the comments section.


  1. Alice. “Perfect Knowledge” V-Mundi, 23 May 2012. Web. 7 January 2016. <>.


Images of cards came from!!_Vanguard_Wiki. These images may have been re-sized.

3 thoughts on “Open Hand, Closed Hand

  1. Should make a note in this article on how to play around such an ideal, as in make sure to play cards that are revealed to your opponent as soon as it is strategically sound to do so, as to remove open cards from your hand, rather than using closed cards and giving your opponent a better idea of what is left in your hand.

    For example, if you check a crit, and you already have a heal in hand, when you go to guard, drop that same crit from hand to guard, and not the heal. This keeps your opponent guessing on what you may, or may not have left in hand. Same when placing RGs. If you check a G2, try and ride it (assuming G1 VG) or call it the next turn, or use it for guard fodder itself, over other options. Again, don’t BLINDLY follow this if you have a certain plan already in motion, but such thoughts can help reduce your opponent’s knowledge using the same theory, rather than using it purely for your gain.


  2. Or I guess I should say MORE into, as I now noticed a VERY small segment of text based around it compared to the rest of the article. I missed it the first readthrough and just now saw it going back.


    • You have made a very good point. The use of information that the player reveals or does not reveal in game is very important. Since you have mentioned this, the plan is to make an article focusing on how information affects the player in game. Thanks for your input.


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