Episode 44

Happy Birthday Time is the twenty-second episode of Season 2 and the forty-fourth episode of the Assassination Classroom anime. It premiered in Japan on June 9, 2016.

Summary
After taking out the army unit stationed inside the mountain, Class 3-E reunite with Korosensei. Their celebrations, including a happy birthday to mark another anniversary of Korosensei and Ms Yukimura meeting for the first time, are brutally cut short by the arrival of Yanagisawa and the second God of Death, now a tentacled monster. The pair then battle Korosensei with the students unable to help.

Plot
With three hours remaining until the orbital laser cannon is charged, Nagisa and the others begin infiltrating the mountain. Using their home turf to their advantage, the students knock out all the police troops guarding the area and reach Korosensei, who praises their efforts for coming so far despite the odds. He calmly shares words of wisdom with his students, preparing them for the road ahead. Just as Nakamura brings out a cake and all the students celebrate Korosensei's birthday, Yanagisawa appears on the scene with The Reaper, who has been powered up with tentacles. Korosensei looks back to when The Reaper used to be his apprentice, but he never gave The Reaper his approval as an assassin. While The Reaper battles Korosensei, Yanagisawa injects himself with the tentacle formula and attacks Korosensei as well.

Anime and Manga differences

 * The anime replaces Craig Houjou and his Wolfpack group with an elite SDF (Self-Defense Force) commander and his battalion of soldiers.

Trivia

 * An Elite SDF Commander was modelled after Kazutaka Shindo, Kunugigaoka's Baseball Captain.