I started reading the webtoon while watching this and it really made me appreciate the drama more. The webtoon was first released over 10 years ago and the drama made updates to tell the story in a more engaging way.

The Good:
They create a contrast in the tone through Kim Chi Yeol's interviews versus the harsh reality that the students are facing. Kim Chi Yeol captures some funny moments of the students at times and in general they have some laid back humorous scenes. However, the worst possible thing happens each episode which immerses us in the students' feelings of being students who want to be playful at times in the midst of adversity. They were supposed to be goofing off from studying for their college entrance exam, not goofing from training to fight a war that literally fell from the sky. They also rewrote some order of events that helped create tension and suspense for the story. In the webtoon, everyone was kind of just going with the flow even when they were faced with a potentially traumatizing moment.

The Bad:
The changes to Bora and Ilha don't make sense to me. I don't get why they were changed to be more bullies. In the webtoon, Ilha seemed more like a class clown which is why he got into the fight that led to the studious Younghoon's death. But here, he's just a bully that is getting screentime without any sort of redemption so far. On the other hand, Bora was fine being a popular girl in the webtoon that redeemed herself by acting upon her sympathy for Aeseol.