NPCs are Computer operated duelists, mostly based on characters from the Yu-Gi-Oh! franchise, but there are also generic NPCs with their own avatars.
They cost one DUELPASS point to duel, but your result does not count towards your overall score; instead a win loss scoreboard is set between yourself and each NPC.
Above each NPCs head is a star. These stars represent your "Friendship Level" with the NPC. The more you duel an NPC, the more stars will appear above their head. Wins will make these stars appear quicker, but losses will also make them appear, albeit at a slower pace. after 6 little stars have appeared, the next duel or two (depending on win/loss) will change it into a single large star. and from there certain NPCs (The character based ones) will allow you to increase their "Friendship Level" by even more. Wins after a Big star will start another set of 6 stars alongside the big star. These will follow the same rules as above until you have collect 3 big stars.
With each set of 9-10 duels against the NPC,(8 or so if you win all your duels against the NPC, 9-10 if you Lose a few) you will receive a gift from the NPC. With characters, this will be a card and a deck recipe for the first and second sets, and a card, deck recipe and avatar part for the third (30ish duels), and with generic NPCs, this will result in a card, recipe and sometimes an avatar part (Depending on the NPC) after the first set.
There are more to NPCs than you think so
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