Sunlit Marsh is a land card from the Magic: The Gathering Secrets of Strixhaven Commander set, classified as an Unknown rarity (#409). It provides colorless mana or can enter the battlefield tapped unless the player controls a Plains or a Swamp, making it a versatile addition to mana bases in various decks. Currently valued at $0.15, it appeals to collectors and players looking to enhance their gameplay strategies while maintaining affordability.