This chapter is dominated by Red's Charmander flame experiment. It also explains briefly what happened to Red's dad. I don't remember anything particular about Rangers in Gen1 -- or, frankly, any of the games I played -- but it gets more elaboration later and makes sense that the role is both elevated in importance and extremely dangerous in this darker take on Pokemon.
The experiment answers the question of how Charmander's Ember fire attack works. The tone of the presentation bothers me though. I've spent an embarrassingly long time trying to articulate why. Two weeks or more -- off and on -- maybe? There's a single word I could use to summarize what bothers me. If you also cringed at "Are you aware of the scientific method?" then you may know what I mean... I think the reason why I can't let it go with just that is that it's also a criticism that I've accused myself of before. I may be able to learn something important about writing or improve myself by exploring it further.
I'm going to leave it at that for now so that I can move on though.