Rock Hydra is a creature card from the Magic: The Gathering Revised set, classified as an Unknown rarity. Valued at $4.15, it features a unique mechanic that allows players to allocate damage to its heads, making it a strategic choice in gameplay. Collectors appreciate its historical significance within the game, as the Revised set is one of the earliest core sets released in Magic’s history. Grading and sales trends indicate steady interest among players and collectors alike.