WARNING - MINOR AND MAJOR SPOILERS FOR THE EPISODE MIGHT FOLLOW.
So before I begin this review let me just mention that I love both earlier mentioned episodes. Especially the first one is truly something special for me and an example how good brave TV can be. This time, Matt Stone and Trey Parker promised us a good, old adventure centric episode in the spirit of earlier seasons. And... that IS basically what we got. However, I don't think that one turned as good as it was supposed to.
As I have stated earlier, the episode easily brings memories of episodes 5x01 and 9x04, which can be pretty good or pretty bad -it depends on the taste of the viewer. As for me however, I prefer when the guys behind South Park let their Imagination go wild instead of remastering old jokes - it is then when we get all time classic episodes, and not only as in "South Park Classic" but as "TV Classic", like the Imaginationland Trilogy or the infamous Scott Tenorman episode, so of course here already lies some of the problem for me. But probably the thing the episode lacked most was pure South Park-ey humour. Sure, we finally have the main four boys in the spotlight together, doing some crazy stuff, what sadly has become an exception in the last few years ( at the other hand - do we? Cartman seems strangely absent, or at least silent for the most part), but the jokes and dialogues between them seemed... forced, even rehashed - again, one of the earliest jokes between Cartman and Kyle really reminded me of the " Sand in the Vagina" from the season 5 premiere. The episode overall was pretty humor-less as for my taste, and at the other hand when they did a decent joke, the creators decided to ruin it by overusing the heck of it. I don't have anything against more serious episodes, in fact I love all of them, even the generally disliked "Stanley's Cup" and I would like to see a darker episode in the upcoming 20th season (which's first episode will air at 14 of september 2016)
The Plot of the episode is a pretty typical alien lost on earth story. Well, except of the war for stuffing thing, and stuffing being one of the most valuable resources in the universe - that is, I admit, a really good play, along with the Indians and Missionaries as aliens plot. However, here comes another problem. We were supposed to get an episode in spirit of the earlier ones. And yes, we did, I admit that. Partially. Because unfortunetly, Matt and Trey decided to put yet ANOTHER pop culture spoof here. The history channel's Ancient Aliens and the movie Thor both become the target of the creators mocking. And this time, in my opinion it was really unneeded. The spoof was not badly executed actually it was really decent, however I think - and at the time of the first viewing really hoped so - we should really get episodes based simply around the boys and their friends/enemies, especially when we are promised to, because really, the new format of movie spoof after tv show spoof after yet another movie spoof can really become boring for some viewers. The part of the episode's plot which was not a parody was a bit better however it too had its flaws. Particurally every decision/action the characters taken was too long for my standards. It actually seemed to me like the creators wanted to make each scene as long as possible because they didn't really have much idea for the episode outside of throwing pop culture references - the scene Natalie Portman was denying opening of the portal, for example. That might have been actually a Thor reference, though, but I don't think that ruins my point- the scene could end much faster and personally irritates me on every rewatch.
So, was "A history Channel Thanksgiving a bad episode? Not exactly - it was simply a rather mediocre watch for me personally, but i fully understand that this episode's type of humour just isn't funny to me, but mighg be for someone who loves references both to pop culture and to the show itself. Part of my dislike might come from the fact that I did not watch Thor, and saw only a couple of episodes of Ancient Aliens - which, I admit made the same sort of "Impression" on me that it did on SP creators. However, might be due to it being the yet another popculture based episode, or because there was too litle of the humour for me - the episode did not appeal to me as good as it should and could have. I am not saying it was weak, I am just saying that what could have been a great episode, turned out to be a mediocre mix of other jokes and episodes. Definitely not one of my most rewatched ones.
My ranking : 6.2/10