why is it called a v card

Dalton Wyatt, a world-renowned scientist and inventor, is transmigrated into the body of a high school student, also named Dalton Wyatt, who had tragically committed suicide due to unfortunate circumstances and a complicated life. The enchanting world of cards he finds himself in is vastly different from Earth, yet eerily similar in certain aspects. Unlike the peaceful Earth, where humans fought only amongst themselves, this new world is plagued by dungeons and monsters. Here, humanity's survival hinges on battling these mythical and legendary creatures. Ordinary mortals lack the strength to stand against such formidable foes. Thankfully, a select few are blessed with the ability to harness their souls, manifest soul power, and become card apprentices—humanity’s last hope against extinction. Card apprentices are individuals who form contracts with grimoires, mystical artifacts that allow them to wield powerful and versatile cards to fend off monsters and conquer dungeons. A grimoire provides card apprentices with abilities such as card creation and card fusion. Most importantly, it enables them to unlock their full potential in card battles. While this world shares the concept of science with Earth, its focus is not on electronics or industrialization. Instead, cards replace the need for most technologies, fulfilling even the smallest of daily necessities. This world revolves entirely around the grimoire’s abilities, particularly card creation and card fusion. Transmigrated to a place where strength can be bought with money, Dr. Wyatt is forced to earn a living to ensure his survival. Fortunately, with his otherworldly knowledge and expertise, card creation comes naturally to him, setting him apart from other card apprentices. Dr. Wyatt crafts and sells perfect, powerful, and resourceful cards, steadily growing stronger in this monster-ridden world. --- "What did you say? Making good cards is hard? Bah! Card creation is a breeze." "My friend, let me enlighten you—there are no 'trash card ingredients,' only incompetent card creationists." [Commencing card creation using ingredients, i)Bloody Veins - G Rank, Mortal Grade ii)Nyon Rope - G Rank, Mortal Grade iii)Common Core - G Rank, Mortal Grade Card creation… complete! Card Name: Bloody Rope Card Type: Item Card Card Rank: E Rank, Common Grade Card Rating: 3 Stars Card Durability: 100/100 Card Effect: The Bloody Rope can bind and incapacitate its target. When in contact with a target’s wound, it triggers paralysis and blood drain effects. Additional Effect: Paralysis, Blood Drain] "This can’t be real! You used G-rank mortal-grade ingredients and yet crafted an E-rank common-grade card with full durability and a three-star rating? This isn’t real—I must still be dreaming! I couldn’t possibly have woken up today—this has to be a dream!"