[DreadBringer]

The Egg is explained as the 101st Chemy, a.k.a Nijigon, watching over Houtaro from the Driver thanks to Fuga. Unlike others, it is capable of actual speech, providing clearer insight into the Chemies for the audience.

At least for Nijigon, Chemies don't necessarily want to harm people and turned into Malgam, contrary to Gigist's claims. However, Nijigon is initially a bit cynical about being born and living, focusing on the negative aspect of Chemies being hurt and is skeptical about Houtaro doing good deeds, wanting him to stay instead.

Houtaro is still fine because he can rely on alchemy's potential to restore Hopper1 and his friends, which is accomplished in his final form, Rainbow Gotchard. Houtaro is established as having mastered alchemy, equating it to cooking, and he can now cook where others enjoy it in Nijigon. The fight, however, is not particularly special, just attacking with a rainbow aura, and a bit of alchemy that isn't really different or more spectacular than previous ones.

As it seems recurring now, Rinne's trait is that she easily succumbs to despair when things get tough, both here when Houtaro is 'locked away' or when Seina was frozen. Even when she gets over the latter, she regresses back here. It doesn't appear often, but Renge is the one who had the most chance of lashing out among the cast (like the next episode against Houtaro in the park), albeit for this one, Rinne is really being weak to Renge's disappointment.