Type
The word "type" has two meanings: 1. A card"s type (and subtype and supertype, if applicable) is printed directly below the ill.u.s.tration on the card, on its type line. Cards, tokens, permanents, and spells all have types. Abilities don"t have types. See rule 205, "Type Line," and rule 212, "Type, Supertype, and Subtype."
When an effect changes an object"s type, the new type replaces all previous types. If the effect is adding a type, or allowing an object to retain its types, it will say so. See rule 212.1c.
2. The "type" of mana is its color, or lack thereof (for colorless mana). See also Mana.
Type Line
The type (and subtype and supertype, if applicable) of a card is printed directly below the ill.u.s.tration. See rule 205, "Type Line," and rule 212, "Type, Supertype, and Subtype."
Type-Changing Effect
A type-changing effect is an effect that changes the type of an object. It"s generated by a type-changing ability. See rule 418.5a.
Unattach
An Aura or Equipment becomes unattached if it was attached to a permanent and then is not. If an Aura or Equipment leaves play while attached to a permanent, it becomes unattached. If a permanent leaves play (unless it phases out) while an Aura or Equipment is attached to it, the Aura or Equipment becomes unattached.
Unblockable
If an attacking creature "is unblockable," no creature can legally block it. Spells or abilities may still cause it to become blocked.
Unblocked
A creature is unblocked if it"s attacking and no creature blocked it during the declare blockers step of the current combat phase. It remains an unblocked creature until an effect causes it to become blocked, it"s removed from combat, it stops being a creature, its controller changes, or the combat phase ends. Unblocked creatures don"t exist outside of the combat phase or before the declare blockers step. See rule 309, "Declare Blockers Step."
Universal Tournament Rules
The DCI Universal Tournament Rules (www.wizards.com/default.asp?x=dci/doccenter/home) cover tournament play for all DCI-sanctioned games, including the Magic game.
Unless
Some cards use the phrase "[Do something] unless you [do something else]." This means the same thing as "You may [do something else]. If you don"t, [do something]."
Untap
To untap a tapped card, rotate it back to the upright position. See also Tap, Tapped, and Untapped.
Untap Step
The untap step is the first step of the beginning phase. All permanents controlled by the active player normally untap at this time. See rule 302, "Untap Step."
Untapped
A permanent that"s upright is untapped. Tapping permanents shows that they"ve been used. Permanents untap during their controllers" untap steps. See also Tap, Tapped, and Untap.
Upkeep Step
The upkeep step is the second step of the beginning phase. Some cards have abilities that trigger at the beginning of the upkeep step; such an ability is informally called an "upkeep cost" or an "upkeep effect." An upkeep cost is usually written in the form "At the beginning of your upkeep, you may [pay cost]. If you don"t, sacrifice [this card]." These are normal triggered abilities-there are no special rules for them. See rule 303, "Upkeep Step."
Vanguard and Avatars
The Vanguard supplements consist of oversized placards and online avatars that modify the game. A Vanguard placard or avatar is selected before the game begins, adjusting a player"s starting and maximum hand size and starting life total. A Vanguard placard or avatar has no color or type, and it can"t be affected by spells or abilities.
Vigilance
Vigilance is a static ability that modifies the rules for the declare attackers step. Attacking doesn"t cause creatures with vigilance to tap. See rule 502.14, "Vigilance."
sWall is a creature type with no particular rules meaning. Many older cards with the Wall creature type have received errata so that they also have the defender ability. Many older cards that referred to the Wall creature type also have errata. Updated wordings for all cards are available in the Oracle card reference.
Win the Game
A game immediately ends when a player wins. See rule 102, "Winning and Losing."
World
World is a supertype that normally applies to enchantments.
If two or more permanents have the supertype world, all except the one that has been a permanent with the world supertype for the shortest amount of time are put into their owners" graveyards. In the event of a tie for the shortest amount of time, all are put into their owners" graveyards. This "world rule" is a state-based effect. See rule 420.5.
If a world permanent"s types or subtypes change, this doesn"t change its supertypes. The permanent will still be a world permanent.