Hoshi no Samidare, Ansatsu Kyoushitsu Recommendations
A being who is planning on destroying the Earth after a set amount of time versus a group of people who are working together to stop him. There is a tremendous amount of group development over the course of both stories, though Hoshi no Samidare has more individual character development with a somewhat smaller group making the characters easier to remember and more likeable. Still, the antagonists' of both stories are also likeable and very overpowered and threatening. Despite them often talking normally with those who oppose their plans to destroy the world, they do not change their minds.