The beginning of combat step is the first step of the combat phase. A player may play spells and abilities during this step whenever he or she has priority. See rule 307, "Beginning of Combat Step."
Beginning Phase
The beginning phase is the first phase of the turn. It has three steps: untap, upkeep, and draw. See rule 301, "Beginning Phase."
Block
A creature blocks when it"s declared as a blocker during the combat phase. See rule 309, "Declare Blockers Step."
Block Alone
A creature is blocking alone when it"s the sole creature controlled by the defending player declared as a blocker in a given combat phase. See rule 306.4.
Blocked Creature
An attacking creature becomes a blocked creature when another creature blocks it or an effect causes it to become blocked during the combat phase. It remains a blocked creature until it"s removed from combat, it stops being a creature, its controller changes, or the combat phase ends. A blocked creature doesn"t become unblocked if the blocking creature is later removed from combat. Blocked creatures don"t exist outside of the combat phase. See rule 309, "Declare Blockers Step."
Blocking Creature
A creature becomes a blocking creature when (a) it"s declared as part of a legal block during the combat phase and (b) all costs to block, if any, have been paid. It remains a blocking creature until it"s removed from combat, it stops being a creature, its controller changes, or the combat phase ends. Blocking creatures don"t exist outside of the combat phase. See rule 309, "Declare Blockers Step."
Bloodthirst
Bloodthirst is a static ability. "Bloodthirst N" means "If an opponent was dealt damage this turn, this permanent comes into play with N +1/+1 counters on it." See rule 502.50, "Bloodthirst."
Bury (Obsolete)
Some older cards were printed with the term "bury," which meant to put a permanent into its owner"s graveyard. In general, cards that were printed with the term "bury" now read, "Destroy [a permanent]. It can"t be regenerated," or "Sacrifice [a permanent]."
Bushido
Bushido is a triggered ability. "Bushido N" means "Whenever this creature blocks or becomes blocked, it gets +N/+N until end of turn." (See rule 309, "Declare Blockers Step.")
Buyback
Buyback appears on some instants and sorceries. It represents two static abilities that function while the spell is on the stack. "Buyback [cost]" means "You may pay an additional [cost] as you play this spell" and "If the buyback cost was paid, put this spell into its owner"s hand instead of into that player"s graveyard as it resolves." Paying a spell"s buyback cost follows the rules for paying additional costs in rules 409.1b and 409.1f-h. See rule 502.16, "Buyback."
Cantrip (Informal)
This is a nickname for any spell that has "Draw a card" as part of its effect.
Card
When a rule or text on a card refers to a "card," it means a Magic card with a Magic card front and the Magic card back. Tokens aren"t considered cards-even a card that represents a token isn"t considered a card for rules purposes. See rule 200.1.
Use the Oracle card reference to determine a card"s text.
Cast (Obsolete)
Some older cards used the term "cast" to describe the playing of a spell. In general, cards that were printed with the term "cast" now use the term "play."
Caster (Obsolete)
Some older cards used the term "caster" to describe the player who played a spell. In general, cards that were printed with the term "caster" now refer to the object"s "controller."
Casting Cost (Obsolete)
Some older cards used the term "casting cost" to describe the mana cost of a spell. In general, cards that were printed with the term "casting cost" now use the term "mana cost." Cards that used the term "total casting cost" now use the term "converted mana cost."
Change a Target
The target of a spell or ability can change only to another legal target. If the target can"t change to another legal target, the original target is unchanged. Changing a spell or ability"s target can"t change its mode. You can change the target of a spell or ability only if an effect tells you to change its target. See rule 415.7, "Changing Targets."
Characteristics
An object"s characteristics are name, mana cost, color, type, subtype, supertype, expansion symbol, rules text, abilities, power, and toughness. Characteristics don"t include any other information, such as whether a permanent is tapped, a spell or permanent"s controller, a spell"s target, what an Aura enchants, and so on. See rule 201, "Characteristics."