Dream Eater Merry - Season 1 Episode 12 Nightmare

As Yumeji and the others grow concerned about Mystletainn's strength, Chizuru brings everyone into her daydream to meet Lestion, who explains that the only way to hurt Mystletainn is a special gun which uses the agony from killed dream demons and the despair from humans as ammo. As Lestion leaves to do his own thing, Engi shows her belief in human dreams due to the extraordinary nature of Merry and Yumeji. Later, Chizuru mentions that Lestion will die if he fires the gun, becoming afraid that her memories with Isana may soon be erased. After the final exams are finished, Ijima comes to the café and Engi brings everyone into her daydream in order to use her home field to her advantage, but Mystletainn kidnaps Isana and summons a large tree. Engi uses her strongest attack on Mystletainn, but she survives and deals a critical blow to her. With Merry similarly outmatched, Yumeji takes Engi's sword and charges towards Mystletainn.