Honestly, the drama and the concept were very good, but I felt that the ending was rushed. I hated the ending as it was tragic and reminded me of DP, like, why couldn't they just give all the remaining kids a good life? Why did they have to die? If they had to die, let them be killed by the aliens, but how did they die due to an idiotic guy who was too stressed and did something stupid? He could have just asked for forgiveness, but he killed most of the students. I also felt that the prison episodes were unnecessary, they could have used that time to find a safe haven or have the kid destroy the last sphere for a good closure, but no, they put in a useless prison episode(s). This series had a lot of tragic and traumatic scenes, but I really liked the acting by the kids who played the students.