I Make Cards in Card World

Waking up with a phone call, Hu Yan found that he had traveled through time! Grandpa left himself a choice of two properties! Got a system for making cards. The world has a new theme. A person's life is related to cards, ID cards, bank cards, meal cards, transportation cards, and battle cards! Etc! What the hell is that last one? Huh? Why are they divided into element cards, beast cards, human cards, elf cards, dragon cards, murloc cards, magic cards, trap cards, equipment cards, weapon cards, space cards, and pet cards. . . There is actually an industry of card holders? Why is my major in mechanical automation?