When two monsters battle, the attacker's Attack Points are compared to the target's Attack or Defense points, depending on what battle position they were in
Commander tip: how many sleeves do you need
In most of the games these are a collection of crystals tied to elements (Wind, Fire, Earth, Water), sometimes Light and Dark, and in other times more abstracted
It includes boosters, lands, storage and accessories, which makes it feel more complete than a few loose packs
Gaia the Dragon Champion X WIND Level 7 [ DragonFusion ] ATK 2600 DEF 2100 "Gaia The Fierce Knight" + "Curse of Dragon" Gaia the Magical Knight X LIGHT Level 7 [ WarriorEffect ] ATK 2300 DEF 2100 (This card is also always treated as a "Gaia The Fierce Knight" card.) If you control no monsters, or your opponent controls a monster with 2300 or more ATK, you can Normal Summon this card without Tributing