361. Conditions, rules, constraints, or statements that affect the course of regular play.

361.1. These abilities have a wide variety of formats to recognize. Example: "I get +1[M] while you have 2 or more cards in your hand." Example: "Friendly Yordles at my battlefield have [Shield]."

361.2. They can be recognized by being statements of fact.

361.3. Passive Abilities can be conditional.

361.3.a. Conditional Passive Abilities can be recognized by the occurrence of "if" or "while" as part of the statement of the ability. Example: " While I'm attacking or defending alone, I have +2 [M]." Example: " If an opponent controls a battlefield, I enter ready."