@fuadhika
My guess is that the author thought the superheated vapor had to be trapped to cause an explosion, hence the chunks of ice as a method of penetration. I'm with you though, my gut feeling tells me the water probably shouldn't have vaporized that quickly/violently because the huge...
@Aichan
Very high levels of optimism and lack of perspective due to being showered with praise all his life. He seems self-aware about his inadequacies but he didn't realize how bad he actually is in comparison to others without his OP light magic. This is a bit clearer in the novel because...