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

How come Yu-Gi-Oh! can collaborate with Type-Moon?
This Type-Moon game is quite well-made; isn't it a bit of a waste to use it for playing cards?
I'm here to play cards, what do you want?
With this much bleeding, how did your game pass censorship?!
Why did they even make a visual novel system?!
What?! This isn't a game, I've traveled to another world?!
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The cards are original creations based on the corresponding legends and abilities. They are essentially card substitutes for battles and will not include cards from the Yu-Gi-Oh! series.
It's not a traditional Yu-Gi-Oh! story; it's just using the card game to bring out related Servants and characters to play.