WARNING! Nerd talk below.
I know that complaining about unrealistic physics in fiction is cringe, BUT, really. I can ignore the floating platforms not moving despite someone stepping on them, which breaks rules established by the manhwa itself: added weight will make them go down. But really, ignoring newtonian laws is too much. Look at the force the pea shooters used, but you want to tell me that the blocks just stood in the air like that? Nuh uh. They would be sent flying away. Any force has an equal, opposite force as a reaction. That's BASIC physics.
Unless the same amount of pea shooters per block that shot at the skeleton shot exactly at the opposite direction, they would have just been sent spinning in the opposite direction of the skeleton. It's ok-ish when these things happen with jumping people, because you can at least make the excuse that they had the momentum from their jump to stop the opposite force. But this is very much not the case here. It was just floating cubes with velocity 0, so they should be launched away after the first shot.
Anyway, rant is done. This manhwa will keep breaking the laws of physics, and so will many more. It's just a fictional story, so nobody should take it this seriously. I'm looking at you, powerscalers.