Lord Gaia the Fierce Knight [MVP1-EN050] Ultra Rare EX1-051 You cannot activate this card

You cannot activate this card if multiple cards with the same name

ignoring this error

using a Dragon monster

Just grab two packs and shuffle them together for wild combos and a fun

Lord Gaia the Fierce Knight [MVP1-EN050] Ultra Rare EX1-051 You cannot activate this cardSet: The Dark Side of Dimensions Movie Pack Card type: Effect Monster Rarity: Ultra Rare Attack: 2300 Defense: 2100 If your opponent controls a monster and you control no monsters, you can Special Summon this card (from your hand). Once per turn, if a monster(s) with ATK higher than this card is Special Summoned to your opponent's field (except during the Damage Step): You can make this card gain 700 ATK until the end of this turn.