How can you identify a triggered ability in a game?

A triggered ability is a specific type of ability in Magic: The Gathering that automatically activates in response to a certain event or condition occurring in the game. The defining feature of triggered abilities is their structure; they typically follow the format of "[Trigger condition], [effect]" and start with the words "when," "whenever," or "at."

Identifying a triggered ability is crucial because it helps players understand when an ability will activate and what effects it will produce. For example, an ability that states, "Whenever a creature enters the battlefield under your control, draw a card," clearly indicates that the effect occurs whenever the specified condition (a creature entering the battlefield) is met.

The other options do not accurately describe the characteristics of triggered abilities. For instance, abilities that start with "cast" or "activate" are typically referring to activated abilities, which require a cost to use and do not trigger automatically based on game events. Verbal announcements are not part of the identification process of triggered abilities, as they are self-contained and do not rely on a player declaring them verbally. Finally, the requirement of a cost to activate refers to activated abilities, not triggered abilities, which do not require any costs to be paid when they trigger.

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