Short summary: Hendricson transforms the soldiers into giant demons (of a size similar to that of Diane). Diane eventually confronts one of those monsters when she reaches the conflict zone between Hendricson and Meliodas.
Short summary: The fight between Diane and the demon continues. Ban helps her and heals her with a "portable spell." Then, Meliodas and Hedricson go to a relatively distant place, reason why Diane goes that new zone of conflict to help. Upon arrival, he confronts Hendricson using his earth powers.
Short summary: The protagonists discover the secret of the power of Hendricson: he has drunk demon blood. Hendricson is sent to an underground area, where he increases his powers by drinking silver demon blood. Then it comes to the surface to face all the soldiers. Diane attacks him, but does almost no harm, so she is hurt. After Hawk's supposed death, Elizabeth released her healing powers, completely curing Diane. That's when Diane and her comrades decide to fight again.
Short summary: The fight continues and Diane attacks with all her strength Hendricson. Until Gowther reappears and uses his psychic powers to communicate a plan that has Meliodas. The plan works and Hendricosn is expired. After that, Diane celebrates the victory and the fact that Hawk was not dead. Afterwards, they are all going to be celebrated, and Diane acquires a "normal size", reason why invites King to be her partner in the celebration. Finally, the capital sins are going to make new adventures, and this time Diane will "not be a nuisance" due to her size.