Battle in the Center of the Mind: Asta engages in this with the demon in his grimoire, who tries to take over his body during his fight with Ladros. He promptly beats it into submission and uses its powers in his "Black Asta" form.
Be Careful What You Wish For: The Witch Queen wanted Vanessa to control destiny when the latter was young. This comes back to haunt her when Vanessa uses her Red Thread of Fate magic to thwart her plans for good.
Deal with the Devil: Subverted with Vanessa's bargain with the Witch Queen. After returning to the Forest of Witches, Vanessa asks the Queen to heal Asta's arms in exchange for her freedom. However, the Queen turns on Vanessa and her friends, and she reveals that she knew her daughter would return to the forest after all. Fortunately, the Queen ultimately keeps her word after she's completely defeated by the newly-manifested Red Thread of Fate.
Demonic Possession: Defied. When the demon inside Asta's Grimoire attempts to take over his body during their Battle in the Center of the Mind and deliver a Curb-Stomp Battle to the resident villain, Asta puts his foot down, climbs up said demon's body, and is implied to have punched said demon into submission, taking the power for himself.
Didn't See That Coming: The Witch Queen does not realize that Vanessa's Red Thread of Fate magic can only be formed from whom she has a bond with. So, when Vanessa's magic stops Asta from killing Noelle and Finral and ultimately thwarts the Witch Queen's plans, the latter becomes puzzled by what has just happened until Vanessa explains it to her.
For Want of a Nail: Both the Witch Queen and Yami Sukehiro ultimately help sow the seeds of this arc along with a certain Yami Sukehiro. The queen traps Vanessa in a birdcage so that the latter can fully realize the potential of her thread magic. Then, Yami unintentially breaks open the birdcage, leading Vanessa to join the Black Bulls. Then, when Asta's arms are seriously injured, Vanessa and her friends seek the Queen's assistance to heal her arms. Later, when the Queen tricks Asta into killing the Black Bulls after they stop the Diamond Kingdom's invasion of the Forest of Witches, Vanessa finally awakens her Red Thread of Fate magic through her bonds with her allies.
Hoist by Her Own Petard: The Witch Queen spent years trying to make Vanessa realize the potential of her thread magic. After Vanessa helps her friends stop the Diamond Kingdom from invading the Forest of Witches, the Queen manages to trick Asta into almost killing the Magic Knights. This triggers Vanessa's latent "red thread of fate" magic to manifest and since it can only be formed from whom Vanessa has a bond with, the Queen's plot is ultimately thwarted.
Hope Spot: Asta and his friends stop the Diamond Kingdom's invasion so that they can make the Witch Queen heal Asta's arms. Unfortunately for them, the Queen instead attempts to trick Asta into killing them all, starting with Noelle and Finral.
Moving the Goalposts: Asta and the Black Bulls try to make a deal with the Witch Queen to heal him and his friends for defending the Forest of Witches against the Diamond Kingdom. But the Queen altered the deal and tricked Asta into almost killing her friends.
Nice Job Breaking It, Hero!: Dominante has Fanzell, Finral, Asta, Noelle and Mariella cover themselves to avoid detection. When they enter the Forest of Witches, they lose their cloaks at the worst possible time, alerting the Security Golems to their presence.
Nice Job Fixing It, Villain!: The Witch Queen manipulating Asta to try killing Noelle and taunting Vanessa over how she would return to the forest one day allows the latter to awaken her Red Thread of Fate magic and defeat the Witch Queen.
Returning from the Forest of Witches after escaping for many years won't exactly give you a hero's welcome. Vanessa finds this out the hard way when her mother, the Witch Queen, tells her that leaving the forest was always pointless.
While Dominante's plan to search for the Witch Queen may be successful, her plans to have Asta, Finral, Fanzell, Noelle and Mariella enter the forest undetected is derailed right from the start. The group enters the Forest of Witches using Dominante's invisibility cloaks, but the boys' cloak gets pulled off by a tree branch. This immediately catches the attention of the Security Golems, and the mages have no choice but to enter the Queen's manor by force.
Remember the New Guy?: Asta and Noelle meet up with a group of three mages, Fanzell, Dominante, and Mariella. Though they have never appeared in the manga before, Asta and Noelle are not only familiar with them, but have apparently already helped them escape from the Diamond Kingdom, and even received trained with them. The characters were originally introduced in a light novel that serves as a side story to the manga.
Resignations Not Accepted: When Vanessa returns to the Forest of Witches after many years, the Witch Queen wastes no time beating the crap out of her. By the end of the Forest of Witches arc, the Queen notes that Vanessa leaving the forest was ultimately pointless.
So Much for Stealth: During their search for the Witch Queen, Dominante provides Asta, Fanzell, Finral, Noelle, and Mariella with invisibility cloaks to enter the Forest of Witches undetected. Unfortunately, they lose their cloaks thanks to Fanzell's actions and quickly catch the attention of the Security Golems and the other witches.
Too Spicy for Yog-Sothoth: The Witch Queen, despite being one of the most powerful villains and an almighty ruler of the Forest of Witches, doesn't seem to know that Vanessa's Red Thread of Fate magic can be formed only from the bonds between her and the Black Bulls, whom she considers her family.
Villainous Breakdown: The Witch Queen has a subdued one when Vanessa's power manifests and stops Asta from killing her friends, to the point that she even tries to use her magic on her own daughter. When she's finally defeated, she remains in total shock and admits defeat.