When compared to the past three episodes, the episode comes off as surprisingly straightforward, albeit with bizarrely-designed guest characters. It would have to be, with the Turtles becoming aware of Krang's existence. It also would establish the tropes that would be with the series until the Red Sky era.
One example would be the first line of villain dialogue in the episode has Krang outright insulting Shredder, and in turn Shredder insults Bebop and Rocksteady once again.
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I'll go ahead and do my mini-rant, so skip the next paragraph underneath the Spoiler tag if it isn't your cup of tea:
Granted, Shredder started the insulting trend from the first episode on, but this episode is where it becomes the most prominent among all the antagonists in Season 1. Speaking of which, it's curious how the first villain scene began with Krang speaking to Shredder in front of Bebop and Rocksteady. Which begs the question from "Enter the Shredder": were the punks aware of Krang's existence? Or, did Krang finally deign to reveal himself to the punks in between "A Thing About Rats" and this episode? It doesn't much matter, except it's a puzzling detail, especially if one ignores off-camera events. The likely explanation could be a plothole, or Wise dedicing not to flesh out such an introduction for time or pacing reasons.
On a slightly more positive example, the episode appears to be the origin of the running gag line, "I thought we were weird-looking." As said by Bebop and to be said many times over (by Dirtbag and others). Which should make for a cute trivia question, should anyone want to view it that way.
I'll focus on the Turtles, the Neutrinos and the Stone Warriors in the next post. I figured to start with the main villains, as it is the most villain-centric episode of Season 1, so far.