Rock

Rock monsters are an often-overlooked Type, though there were many released in The Lost Millennium series. Usually, Rock monsters belong to the EARTH Attribute and possess high DEF and defense-related Card Effects. A significant number of Rock monsters have effects related to Flip Summoning or have the ability to flip themselves face-down again.

Archetypes include Monk, Piece Golem, the Hex-Sealed Fusion family, and Sphinx cards.

Some of the more notable cards include: "Exxod, Master of The Guard", "Valkyrion the Magna Warrior","Gigantes", "Legendary Jujitsu Master", "Multiple Piece Golem", "Megarock Dragon", "Mine Golem", "Moai Interceptor Cannons", "Muka Muka", "Neo-Spacian Grand Mole", "Sand Moth", "Stone Statue of the Aztecs", "Granmarg the Rock Monarch", "Rockstone Warrior","Enraged Muka Muka" and "Castle Gate".

Four Field Spell Cards exist that work particularly well with Rock monsters. "Wasteland" increases the ATK and DEF of Rock monsters by 200, "Canyon" inflicts double Battle Damage to anyone attacking a Defense Position Rock monster with a weaker monster, "Gaia Power" increases the ATK of EARTH monsters by 500 points, though it weakens their DEF, which is often an important part of Rock Monsters' strategy, and "Acidic Downpour" which is the reverse of "Gaia Power", decreasing their ATK by 500 but makes them gain 400 DEF. Chorus of Sanctuary can be used as an alternative to Acidic Downpour. Rock-Type monsters are also weak against the card, "Breath of Light".

They also have their own Structure Deck, Structure Deck 7: Invincible Fortress.