WARNING: The following contains spoilers for The Seven Deadly Sins: Dragon's Judgment Part 2, now streaming on Netflix.
"Farewell, Seven Deadly Sins" is perhaps the best episode in all of The Seven Deadly Sins. In the second episode of Dragon' Judgment, Part Two, the Sins spend the episode celebrating the (apparent) defeat of the Demon King, only for tragedy to strike when it becomes clear that Meliodas is going to disappear from the world. The saddest episode of the series, the relationships between the Seven Deadly Sins carry this actionless masterpiece.
The power that Meliodas acquired by defeating the Demon King has thrown the world out of balance, and now the only way for Meliodas to save the world is to leave it. At the start of the episode, only Ban and Elaine know about Meliodas' predicament, as the captain doesn't want to burden anyone else with his harsh fate. The happy, playful moments throughout the episode are underscored by the weight of Meliodas' secret, as he tries to soak in one final day with his friends before he has to return to the Demon Realm.
The Sins spend the day prepping for a large celebration, and the women make tea while the men go hunting for food. As the two groups talk, it becomes clear that everyone can sense that something is off with Meliodas and that they have been pretending to be unaware so that they won't have to deal with the pain. Meliodas reveals that he can’t bear to tell Elizabeth about his fate, while Elizabeth reveals that she already knows. The two groups emotionally continue their preparations for their party, knowing that the situation can't be helped.
When King Bartra shocks everyone by offering Meliodas and Elizabeth the Throne of Liones, Elizabeth shocks everyone even more with her refusal of her father's offer, declaring that she will be traveling to the Demon Realm with Meliodas. Later that night, Elizabeth and Elaine discuss her decision privately while the Seven Deadly Sins share a drink inside the Boar Hat. Meliodas tries to play it off by saying he wishes he could see his and Ban's kids fight, but is overcome with emotion over all the things he will miss out on.
The reason this episode is one of the series' best is that it's one of the rare instances of the entire Seven Deadly Sins spending a whole episode together. The various relationships among the Sins have always been the series' greatest strength, and this episode is nothing but emotional character interactions from start to finish. Despite the somber tone of the episode, it's rewarding to see the Sins together after so much turmoil throughout the series, and their love for one another has never been clearer.
This episode is also helped by the lack of action, meaning there's none of the series' notoriously bad animation to distract from the story. The Seven Deadly Sins is at its best when the characters are the centerpiece of the story, rather than a calamitous battle. The series has suffered in the past from trying to cover too many characters, and this intimate episode focused solely on the main cast is much needed in the series' final days. As Meliodas and Ban share one last fist bump, there are smiles all around as the Seven Deadly Sins have reaffirmed that their bonds are eternal.