Artifact

Artifacts represent magical items, animated constructs, pieces of equipment, or other objects and devices. Like enchantments, artifacts remain in play until something removes them. Artifacts are distinct from other cards in that they are colorless, and can be played using any color or colors of mana.

Many artifacts are also creatures; they may attack and defend as other creatures, and are affected by anything that affects either artifacts or creatures.

Some artifacts are Equipment. Equipment cards come into play just like any other artifact, but may be attached to creatures using their Equip ability. Unlike Auras, however, if an Equipment is attached to a creature and the creature is killed, the Equipment stays in play.

From the Comprehensive Rules:

• 212.2. Artifacts
• 212.2a A player may play an artifact card from his or her hand during a main phase of his or her turn, when he or she has priority and the stack is empty. Playing an artifact as a spell uses the stack. (See rule 409, "Playing Spells and Activated Abilities.")
• 212.2b When an artifact spell resolves, its controller puts it into play under his or her control.
• 212.2c Artifact subtypes are always a single word and are listed after a long dash: "Artifact - Equipment." Artifact subtypes are also called artifact types. Artifacts may have multiple subtypes.
• 212.2d Artifacts have no characteristics specific to their type. Because artifacts have no colored mana in their mana costs, they're colorless. Effects can give artifacts one or more colors, however, and colored objects can become artifacts without losing any colors they had.
• 212.2e Artifact creatures combine the characteristics of both the creature and artifact types and are subject to spells and abilities that affect either or both types.
• 212.2f Artifact lands combine the characteristics of both the land and artifact types, and are subject to spells and abilities that affect either or both types. Artifact lands can only be played as lands. They can't be played as spells.
• 212.2g Some artifacts have the subtype "Equipment." An Equipment can be attached to a creature. It can't legally be attached to an object that isn't a creature.
• 212.2h An Equipment is played and comes into play just like any other artifact. An Equipment doesn't come into play attached to a creature. The equip keyword ability moves the Equipment onto a creature you control (see rule 502.33, "Equip"). Control of the creature matters only when the equip ability is played and when it resolves. The creature to which the Equipment is to be moved must be able to be equipped by it. If it can't, the Equipment doesn't move.
• 212.2i An Equipment that's also a creature can't equip a creature. Equipment that loses the subtype "Equipment" can't equip a creature. An Equipment can't equip itself. An Equipment that equips an illegal or nonexistent permanent becomes unattached from that permanent but remains in play. (This is a state-based effect. See rule 420.)
• 212.2j The creature an Equipment is attached to is called the "equipped creature." The Equipment is attached to, or "equips," that creature.
• 212.2k An Equipment's controller is separate from the equipped creature's controller; the two need not be the same. Changing control of the creature doesn't change control of the Equipment, and vice versa. Only the Equipment's controller can play its abilities. However, if the Equipment adds an ability to the equipped creature (with "gains" or "has"), the equipped creature's controller is the only one who can play that ability.