It's a completely guided set of matches
1x Near Mint Mew 025/025 Secret Rare Pokemon Card from the main set of the Celebrations 25th Anniversary Collection
They have performed very well at all of the higher level events of the format, primarily due to their high degree of consistency

Tetran" #6499 "Nanobreaker" #6500 "Rapid-Fire Magician" #6505 "Goldd, Wu-Lord of Dark World" #6506 "Scarr, Scout of Dark World" #6507 "Familiar-Possessed - Aussa" #6508 "Familiar-Possessed - Eria" #6509 "Familiar-Possessed - Hiita" #6510 "Familiar-Possessed - Wynn" #6511 "Pot of Avarice" #6512 "Dark World Lightning" #6513 "Branch!" #6514 "Boss Rush" #6515 "Gateway to Dark World" #6516 "The Forces of Darkness" #6517 "Dark Deal" #6518 "Simultaneous Loss" #6519 "Weed Out" #6521 "Roll Out!" #6522 "Non-Fusion Area" #6523 "Level Limit - Area A" #6524 "Armed Changer" #6527 "Elemental Hero Necroshade" #6528 "Hero Ring" #6529 "Elemental Hero Madballman" #6530 "Dark Eradicator Warlock" #6531 "Mythical Beast Cerberus" #6532 "Magical Blast" #6533 "King of Destruction - Xexex" #6534 "Queen of Fate - Eternia" #6535 "Elemental Hero Steam Healer" #6536 "Burst Return" #6537 "Bubble Blaster" #6538 "Bubble Illusion" #6539 "Clay Charge" #6540 "Armed Dragon LV10" #6541 "Magical Mallet" #6542 "Inferno Reckless Summon" #6543 "Ring of Defense" #6544 "The Grave of Enkindling" #6545 "Rancer Dragonute" #6546 "Mistobody" #6547 "Axe Dragonute" #6550 "White Horns D." #6563 "Uria, Lord of Searing Flames" #6565 "Raviel, Lord of Phantasms" #6566 "Elemental Hero Neo Bubbleman" #6567 "Hero Kid" #6568 "Cyber Barrier Dragon" #6569 "Cyber Laser Dragon" #6570 "Ancient Gear" #6571 "Hero Heart" #6572 "Magnet Circle LV2" #6573 "Ancient Gear Factory" #6574 "Ancient Gear Drill" #6575 "Phantasmal Martyrs" #6576 "Cyclone Boomerang" #6577 "Photon Generator Unit" #6578 "Ancient Gear Castle" #6580 "Miracle Kids" #6581 "Attack Reflector Unit" #6582 "Damage Condenser" #6583 "Treasure Map" #6584 "Hero Spirit" #6586 "Phantasmal Martyr Token" #6587 "Ancient Gear Cannon" #6588 "Proto-Cyber Dragon" #6589 "Adhesive Explosive" #6590 "Machine King Prototype" #6591 "B.E.S

(Translation) Hatakeyama & Kubo (2000), p
Its one thing for a combo to win a game and end it, but the worst banned cards will stop your opponents from doing anything from early in the game (think about cheating out a Sundering Titan on turn 1), but wont let you win for a long time