slave Isekai - yugioh system

A wealthy western teenager finally manages to convince his parents to pay for a trip to a Japanese school, Daniel has finally arrived in Japan to get a cute girlfriend but on the first day of school a magical cycle appears transporting the entire school to the wonderful isekai

"I finally realized my dream, I'm going to have a harem of beautiful elves" Daniel

"Wait, where are the king and princess to welcome us? Why am I chained? What the fuck am I becoming a slave"

Not just Daniel, but all Japanese students were summoned not to be heroes, but to be workers in a magical iron mine.

After years of being a slave, Daniel finally gets a card system from Yu-gi-oh