Any time there is an error in a game that you notice and your opponent does not, you should always notify a tournament official in order to fix the problem. It can be as simple as tapping the wrong mana to cast a spell, or putting a card in the graveyard when it should’ve gone somewhere else. Both players are responsible to make sure errors are avoided and/or noticed when they occur. If you intentionally don’t say anything when you see your opponent make an illegal play because it will benefit you, that’s an easy way to earn yourself a DQ for Cheating – Fraud at any Rules Enforcement Level (from FNM to the Pro Tour).

For example, a player casts Black Sun’s Zenith and puts it in his graveyard instead of shuffling it into his deck, and you notice but don’t say anything. Later in the game, you cast Surgical Extraction targeting the Black Sun’s Zenith. The player who put that in his graveyard notices that it shouldn’t have been there and notifies a tournament official. Through investigation, the judge determines that you noticed the error but didn’t call attention to it because you knew it was to your benefit.

The investigation is important, because we don’t disqualify players who make unintentional errors or honestly miss an opponent’s errors.

Today’s Tournament Tip written by
Ronny Alvarado, Level 2 judge from Houston, TX