Hidden Information (Informal)
Some information within a Magic game isn"t known by all players. For example, face-down cards in any zone and the contents of players" libraries and hands are hidden information. If an effect "reveals" a card that"s normally hidden, the card is public information as long as it remains revealed. See also Public Information.
Horsemanship
Horsemanship is an evasion ability. A creature with horsemanship can"t be blocked by creatures without horsemanship. A creature with horsemanship can block a creature with or without horsemanship. See rule 502.17, "Horsemanship."
Hybrid Mana Symbols
Each of the hybrid mana symbols represents a cost which can be paid with one of two colors: {W/U} in a cost can be paid with either white or blue mana, {W/B} white or black, {U/B} blue or black, {U/R} blue or red, {B/R} black or red, {B/G} black or green, {R/G} red or green, {R/W} red or white, {G/W} green or white, and {G/U} green or blue. (A previous version of these rules referred to hybrid mana symbols as half-half mana symbols.)
If
See "Intervening "If" Clause."
Illegal Action
If a player realizes that he or she can"t legally take an action after starting to do so, the entire action is reversed and any payments already made are canceled. No abilities trigger and no effects apply as a result of an undone action. When reversing illegal spells and abilities, the player who had priority retains it and may take another action or pa.s.s. The player may redo the reversed action in a legal way or take any other action allowed by the rules. See rule 422, "Handling Illegal Actions."
Illegal Target
If a spell or ability specifies targets, it checks whether the targets are legal when it resolves. A target that"s removed from play, or from the zone designated by the spell or ability, is illegal. A target may also become illegal if its characteristics changed since the spell or ability was played or if an effect changed the text of the spell. See rule 413.2a.
Ill.u.s.tration
The ill.u.s.tration is printed on the upper half of a card and has no game significance. See rule 204, "Ill.u.s.tration."
Ill.u.s.tration Credit
The ill.u.s.tration credit for a card is printed directly below the text box. The credit has no effect on game play. See rule 209, "Ill.u.s.tration Credit."
Imprint
Imprint is an activated or triggered ability, written "Imprint [text]," where "[text]" is an activated or triggered ability. Cards that are in the removed-from-the-game zone because they were removed from the game by an imprint ability are imprinted on the source of that ability. See rule 502.34, "Imprint."
Imprinted [type] card
The phrase "imprinted [type] card" means the card of that type that"s imprinted on the permanent. If a permanent has more than one card of that type imprinted on it, each of those cards is an "imprinted [type] card." See rule 502.34, "Imprint."
In Play
In play is the zone in which permanents exist. When an artifact, creature, or enchantment spell resolves, it"s put into the in-play zone as a permanent. When a land is played, it"s put into the in-play zone as a permanent. Tokens also exist in this zone. See rule 217, "Zones."
Independent
An effect is said to "depend on" another if it is applied at the same time as the other effect, and applying the other would change the text or the existence of the first effect, what it applies to, or what it does to any of the things it applies to. Otherwise, the effect is considered to be independent of the first effect. See rule 418.5, "Interaction of Continuous Effects."
Indestructible
If a permanent is indestructible, rules and effects can"t destroy it. Such permanents are not destroyed by lethal damage, and they ignore the lethal-damage state-based effect (see rule 420.5c). Rules or effects may cause an indestructible permanent to be sacrificed, put into a graveyard, or removed from the game.
Infinity Rule (Informal)
There"s no such thing as "infinity" in Magic rules. Occasionally the game can get into a state where a set of actions could be repeated forever. The "infinity rule" governs how to break such loops. See rule 421, "Handling "Infinite" Loops."
Instant
Instant is a type. A player may play instants whenever he or she has priority. An instant spell is put into its owner"s graveyard as the last step of its resolution. See rule 212.5, "Instants," and rule 409, "Playing Spells and Activated Abilities."
Instant Type
Instant subtypes are always a single word and are listed after a long dash: "Instant Arcane." Instant subtypes are also called instant types. An instant subtype that"s also a sorcery subtype is also called a spell type.
The list of instant types, updated through the Time Spiral set, is as follows: Arcane.
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