What must a player do if they notice an error in their life total?

When a player notices an error in their life total, the proper course of action is to inform a judge immediately. This is critical for maintaining the integrity of the game and ensuring that any discrepancies are addressed according to the official rules.

Judges have the training and authority to investigate and resolve issues regarding life totals and other game states. This helps in making sure that the game continues fairly and that all players are following the correct procedures. By notifying a judge, the player allows for any necessary adjustments to be made in a manner consistent with the tournament rules, including those rules governing life total discrepancies.

Attempting to resolve the issue independently, informing the opponent, or ignoring the error could lead to further complications, misunderstandings, or even penalties, and may not result in a fair resolution. Therefore, seeking the assistance of a judge is the most appropriate and responsible action to take in this situation.