Mental Magic is a Magic variant in which the players use normal Magic cards, but have to pretend that each card is actually something else while it's being used. There are some fairly well-known rules for how to go about this; independently, Laurie Cheers and Zoë Stephenson came up with the variant described here.

• Zones in which players may pretend that cards are other than what they appear to be are called "Mental Zones." The in-play zone, the phased-out zone and the stack are all Mental zones.
• In Mental zones, each card has an imaginary alter-ego. The card is treated as though it were instead that imaginary card.
• When a card moves into a Mental zone from a non-Mental zone, the player that moves the card chooses its alter-ego, called binding the card. A card moving from one Mental zone to another keeps the same binding. A card that leaves a Mental zone for a non-Mental zone loses its binding and reverts to its normal self. So, for example, when you announce a spell and put the card onto the stack from your hand, you bind it as you put it there. The choices you can make to bind a card are further limited by the binding rules, outlined below.
• The alter-ego of a card must be legal for the zone to which it is going. So, when putting a card from your hand on the stack, it has to become a spell card. When putting a card from your hand into play, it has to become a permanent card.

The following notes clarify these rules:

• Tokens are unaffected, they're not cards.
• Copying something copies its alter-ego if it has one.
• Binding a spell happens before you choose how to pay its cost, so you may pay using alternate costs.
• Certain abilities specify cards of a particular type. The type is that of the alter-ego if there is one, otherwise the natural type. The type does not have to stay the same across Mental/non-Mental zone changes. As an example, the Hell's Caretaker ability may be used to sacrifice a card that has a creature alter-ego, and get a creature card from the graveyard into play as any type of permanent.
• When searching for cards with the same name as a card in play (for things like Mask of the Mimic, Eradicate, Bifurcate etc...) you use the alter-ego name.
• You only get to bind once. For example, playing a card from your hand to the stack and binding it as a Clone is allowed, but then when it gets into play, it will be a Clone of the alter-ego of an existing card, and won't get bound again as it comes into play.

The rules that specify which cards may be bound as which other alter-egos are the binding rules. There are general rules, followed by specific variants.

General Rules

• Once an alter-ego is chosen for a card, that alter-ego cannot be chosen again that game.
• Alter-egos behave like the Oracle version of that card.
• Cards belong to binding classes, groups of cards that work as each others' alter-egos. Each member of a class may be bound into any other member of that class.
• Players may play any card as a basic land card that counts as all basic land types and has all basic land card names, simultaneously. The card is put into play face-down.

Standard Binding

• A land card shares a binding class with all other nonbasic land cards.
• A nonland card shares a binding class with all the other cards that have exactly the same written mana cost. So, examples from one class would be Disintegrate, Lava Burst, Ghitu Fire, Illuminate, Detonate, Dwarven Catapult - all cards that have the mana cost of XR.
• (Optional) The written mana cost on a card may be altered for the purposes of binding. The different ways of altering a cost are as follows:
• Discard a card to change a colored mana symbol to one of those in the cost of the card you discard. You can't change all of the colored mana symbols in a card's mana cost.
• Discard a card to convert an X-cost into a fixed generic cost equal to the converted mana cost of the discarded card.
• Discard a card to convert a fixed generic cost into an X-cost; the amount you pay for X must be the same as the converted mana cost of the discarded card.

Alphabet Binding

• A land card shares a binding class with all other land cards.
• A nonland card shares a binding class with all the other cards that have the same first letter and the same amount of colored mana in the cost.
• For added variety, try same first letter and same generic cost, or same first letter and same amount of generic and same amount of colored cost.