What happens if a trigger condition is met, but the object that triggered it is not visible to all players?

When a trigger condition is met but the object that caused the trigger is not visible to all players, the ability will not trigger at all. In Magic: The Gathering, transparency is crucial to ensure that all players are aware of the game state and the effects that might occur. If some players cannot see the object that triggered the ability, they cannot properly acknowledge or respond to it.

For instance, if a card has a hidden or private condition that results in a trigger, players who are unaware of that condition cannot act on or react to it appropriately, and thus the game state remains unchanged. This enforcement of visibility ensures fairness and understanding among all participants in the game. Triggers must have clear and visible sources; otherwise, they simply do not resolve.