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castTo cast a spell is to take it from the zone it’s in (usually the hand), put it on the stack, and pay its costs, so that it will eventually resolve and have its effect. A player may cast a spell if they have priority. See rule 601, “Casting Spells.”
To cast a card is to cast it as a spell. (CR 701.5) Keeper of the Yellow Hat during your first seven turns of the game. (Keep track if you're playing with this!)
When The Keeper of the Yellow Hat
enters the battlefieldShort for entering the battlefield. (CR 700.15),
createTo create one or more tokens with certain characteristics, put the specified number of tokens with the specified characteristics onto the battlefield.
If a replacement effect applies to a token being created, that effect applies before considering any continuous effects that will modify the characteristics of that token. If a replacement effect applies to a token entering the battlefield, that effect applies after considering any continuous effects that will modify the characteristics of that token.
Previously, an effect that created tokens instructed a player to “put [those tokens] onto the battlefield.” Cards that were printed with that text have received errata in the Oracle card reference so they now “create” those tokens. (CR 701.7) a legendary artifact equipment token named Yellow Hat with
equipEquip is an activated ability of Equipment cards. “Equip [cost]” means “[Cost]: Attach this permanent to target creature you control. Activate only as a sorcery.”
For more information about Equipment, see rule 301, “Artifacts.”
Equip abilities may further restrict what creatures may be chosen as legal targets. Such restrictions usually appear in the form “Equip [quality]” or “Equip [quality] creature.” These equip abilities may legally target only a creature that’s controlled by the player activating the ability and that has the chosen quality. Additional restrictions for an equip ability don’t restrict what the Equipment may be attached to.
If a permanent has multiple equip abilities, any of its equip abilities may be activated.
“Equip planeswalker” is a variant of the equip ability. “Equip planeswalker [cost]” means “[Cost]: Attach this permanent to target planeswalker you control as though that planeswalker were a creature. Activate only as a sorcery.” (CR 702.6) and "Equipped creature gets +4/+4 and gains
lifelinkLifelink is a static ability.
Damage dealt by a source with lifelink causes that source’s controller, or its owner if it has no controller, to gain that much life (in addition to any other results that damage causes). See rule 120.3.
If an object is no longer in the zone it’s expected to be in as an effect causes it to deal damage, its last known information is used to determine whether it had lifelink.
The lifelink rules function no matter what zone an object with lifelink deals damage from.
If multiple sources with lifelink deal damage at the same time, they cause separate life gain events (see rules 119.9–10).
Multiple instances of lifelink on the same object are redundant. (CR 702.15)."