She is one of Yugis ace monsters that support his main boss monster Dark Magician and the Dark Magician archetype
And then, as a Quick Effect, you can banish it to Synchro Summon an actual Red Dragon Archfiend from your Extra Deck, double its ATK, and make it immune to your opponents destruction effects
To pay him back, she gave him her access six Star Chips, saying that in return he must Duel her in the castle
If you have a Gate Guardian Monster on your side of the field, you can use this to halve your opponents life points, then add it as attack for one of your Gate Guardians
Any tool promising a guaranteed grade from a phone photo is overselling
Your opponent has cast a weirdly outdated board wipe, and you're busy wondering why it isn't a Vanquish the Horde