In Arata/Shinobu side, Shinobu first throw out her fighting words that in the end the strongest players left are ones who play by themselves and they'll settle this match to determine who is stronger and show that they don't need friends or partners. Then Arata just reply with a simple "really?" with his usual smile.
Before the match, during the card setting phase, Arata reminisce to himself and quoting that the way Shinobu is picking her cards and the ways she lays them out and remembering the card location feels nostalgic to him. He then comment internally that Shinobu must have been still playing by herself and treats all 100 cards as her friends.
We then got a quick, rare thought from Shinobu. She was talking to the card and told them she'll take them home really quick in a hide-'n-seek way.
After match starts, Shinobu got the first two cards. Most on-lookers just assume Shinobu is doing her thing but the stuff (high level players) all thought both cards were simultaneously touched and the reason Arata didn't move was because both cards are in Shinobu's territory.
Then Arata has another thought and state that Shinobu is just as fast and precise as he remembered. Then a quick flashback where his grandpa is telling him that the best way to destroy an opponent is to beat him/her at the area they were the best in.
Arata then used a technique that shocked the crowd (don't know how to call it because I'm reading Chinese translations) and took a card from a shocked Shinobu.
The head organizer (the oldest guy in that competition) then thought that Arata reminded him of Arata's grandpa who used to play in that same, incredibly annoying way.
Then another organizer mentioned that the card Arata took was Shinobu's favorite and her best card and this happens after Arata forced two double-touches in her territory and noted that Shinobu must have notice by now that Arata is not an easy opponent.
Then shifts back to Shinobu, where she thought to herself that defending her territory on all side is too dangerous . Then she thought to herself by telling the card that she's sorry because today she'll need to separate the cards from those that she want and those she'll need to throw away.
Then Arata thinks.....Shinobu.....is slowly breaking down...with an calm, evil smile