Why fight the Holy Grail War? Let's play cards!

How come your Yu-Gi-Oh can collaborate with Type-Moon?
The completion level of this Type-Moon game is a bit high. Isn't it a bit of a waste to use it for playing cards?
I'm here to play cards, what are you doing!
With this amount of bleeding, how did your game pass review!
Why even the gal system was made!
What! This isn't a game, I traveled through time?!
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The cards are original creations based on corresponding legends and abilities. In essence, cards replace battles, and no cards from the original Yu-Gi-Oh game will appear.
It's not an orthodox Yu-Gi-Oh novel, it just uses playing cards to attract related servants and people to play.