A quick note: a Magic: The Gathering card is defined as having a Magic card front and back, typically with the brown almost book-like design on the back, with exceptions for double-sided cards
As far as actual utility for this blade goes, it's fun to pay 7 mana for the gimmick, but you shouldnt expect this sword to go off super consistently
The beauty of collectible cards is that even when new cards come out, the old ones are still valuable in their own ways
Limited Cards Limited Astrograph Sorcerer X DARK Level 7 [ Spellcaster / PendulumEffect ] ATK 2500 DEF 2000 P Scale 1 During your Main Phase: You can destroy this card, and if you do, take 1 "Stargazer Magician" from your hand or Deck, and either place it in your Pendulum Zone or Special Summon it
As such, it is no surprise that Kaiba was able to acquire one of the most broken Spells ever created, one so powerful it had to be completely rewritten when brought to the TCG