Just a minor quibble, really. How many episodes do people feel it takes before the “establishing story arc” is complete?
As I see it, the standard arguments are for 2 or 4 (based on the feature length versions of “Exodus”), but I’ve always felt it’s 6 - up to and including “Pumm-Ra”.
My reasoning? Simply the way “Pumm-Ra” ends, with Mumm-Ra really stating his case to the Thundercats (as opposed to “The Unholy Alliance”, where they just see him flying off), setting up a whole series of conflicts between them.
It could also be argued that the Warrior Maidens are the Thundercats’ main allies, and their introduction in “Trouble With Time” is significant, or even the point of thundrillium for fuel in both “Trouble With Time” and “Pumm-Ra” (although on that logic you could say the introduction of thundrainium takes the establishing arc up to “The Ghost Warrior”).
In any case, I’ve always viewed the first six episodes as the whole establishing story.