Hidden information

Hidden information in Magic: The Gathering concerns information that is only available to one player. Some mechanics may force that player to reveal that information.

Description

Unlike for example Chess, Magic is designed with hidden information so that players can surprise one another. In the aspects of variance and hidden information, Magic more closely resembles games played with a standard deck of playing cards, like Bridge. The “gotcha moments” often come from the instants. Your opponent makes what he believes to be an intelligent block and you get to reveal your Giant Growth with a big smile.

Hidden information is an important aspect of gameplay. When an opponent knows everything in your hand, it requires a lot more thought to make sure they're thinking through every possible combination of effects. It also removes any chance of surprise. The hand is hidden because it allows for fun moments where you get to surprise your opponents, and it keeps them from having to track that. In general, hidden information creates less board complexity and allows for more compelling game moments.

If too much of your set is all public information, it makes the game computational. That is, you can plan out future turns in your head. The game gets extra Spike-y and slower because players must keep track of all the information. By having something hidden (usually in the hand), you are adding in an unknown element that allows players to react more in the moment, which, for most players, is more fun. R&D tries to make sure that sets have some amount of hidden information.

Because cards have variance based on where in the game they are drawn, they make sure that there are always good and bad draws. This swing in utility allows players who are behind to make dramatic comebacks. In addition, because the draws are hidden information it helps keep players in the game because there is always the hope of drawing a card that will swing the game in their favor.

In addition to the variance aspects of the game, there's also uncertainty in that you don't know what cards your opponent has in his or her hand or library. Often, you'll face situations where one choice is better if your opponent has a removal spell, while another choice is better if he or she does not. You might have a powerful spell to cast, but you'd rather wait on it if your opponent has Dissipate.

Examples of hidden information

• Cards in hidden zones:
  • Hand
  • Library
• Cards with Face down mechanics
  • Cloak
  • Disguise
  • Foretell
  • Manifest
  • Megamorph
  • Morph

Rules

From the Tournament Rules (May 13, 2024—Outlaws of Thunder Junction)

• 3.13 Hidden Information
  Hidden information refers to the faces of cards and other objects at which the rules of the game and format do not allow you to look.
  
  Throughout the match, a draft, and pregame procedures, players are responsible for keeping their cards above the level of the playing surface and for making reasonable efforts to prevent hidden information from being revealed. However, players may choose to reveal their hands or any other hidden information available to them, unless specifically prohibited by the rules. Players must not actively attempt to gain information hidden from them but are not required to inform opponents who are accidentally revealing hidden information.