(2) Once per turn, if an opponent's monster attacks, during damage calculation, OR, when your opponent activates a monster effect on the field (Quick Effect): You can add to your hand, or Special Summon, 1 "Dark Magician" or 1 monster with 300 ATK/200 DEF from your Deck or GY, then you can change that opponent's monster's ATK to 0
If the opponent controls a monster whose ATK is higher than the ATK of Number 9: Dyson Sphere, its controller can use its detach effect to enable Dyson Sphere to make a direct attack on the opponent that turn
It is not as important in normal Centur-Ion decks
All in holographic form, so some nice rarity increases for classic cards, too.
The process of crafting cards in YuGiOh Master Duel is a bit complicated
The card is cast from exile, and so try and avoid taking Vampires with it that you would've otherwise played from your hand with Strefan, but anything like a removal spell or enchantment is an excellent pick.