Are players required to use sleeves when presenting their decks?

Players are indeed required to use sleeves when presenting their decks in sanctioned Magic: The Gathering tournaments, and it is essential that all sleeves are consistent and free of markings. This requirement helps maintain the integrity of the game by ensuring that no player has an advantage through the use of altered or marked cards. Using sleeves protects the cards from wear and damage over the course of the event, which can happen during shuffling and handling. Additionally, having all sleeves be uniform prevents any potential issues where players might be able to identify cards based on the appearance of sleeves, which can lead to cheating or unintentional game errors. Overall, this promotes a fair and level playing environment for all participants in the tournament.