Frankly, I think the whole basement mystery is what killed the series. That, and the truth behind the titans, and their serum.
The origins of the titans, and what the outside world was like should've remained unsolved.
Man I remember when the Titans were this scientific anomaly that had Hange so excited studying them and documenting their behaviours and weaknesses. Where did they come from? Were they created or did they evolve?
If you had told me that we'd get to a point where it's just as simple as slurping some spine juice while some giant baboon screams I would've told you you were crazy.
Tbh I think something as simple as bio engineering would've been a satisfactory explanation for the origin of the Titans. It didn't have to be anything major given that they were only a part of the mysteries of their world. I actually liked the shift from them to humans as the actual threat a la Jurassic Park. The problem was this whole retarded ancient evil monster plot.
Maybe leaving it a mystery may have been good for the series, but I personally think it's a weak choice that might be even worse in the hands of someone like Isayama. Basically he could do all the shit he's already done, but then not have to explain any of it because "it's a mystery".
Funny you mentioned the Mystery Box, I just watched Billiam's 8-hours Lost Videos (and it's still not over yet) and I just finally understand the fatal flaw of JJ Abrams' Mystery Box. Its a method that only served to prolong a story indefinitely, not to tell a story with ending. And though it might be good to create a shared sandbox storytelling, it also requires active collaboration with other participants. Abrams failed that when he ditched Lost and just hand the wheel to Damon and Carlton, forcing them to come up with explanations when they wanted to finish the series
Back to Isayama though, it felt that a lot of the mysteries in the series, especially after the timeskip, only exist to make the story longer. That's why the answers and explanations are weird or outright ridiculous, he never had any intention to end it
I watched Billiam's vids (think the series is at 9+ hours now). I liked it just for the sheer depth he went into, but imo he was very kind to all 3 of JJ, Damon and Carlton. They fell prey to the old "I must subvert expectations at all costs" bug that seems to hit showrunners of popular series. I'm curious to see if he'll cover their contributions to the massive shitshow that Lost became in the next video.
I think the fatal flaw of the mystery box is that JJ can't write for shit. Mystery box as a concept is retarded anyway. You're gonna have to open it eventually, so what kind of idiot would assume an audience would be satisfied just never finding out what the mystery is? It's like a chef puts a dish on the stove and expects the customer to just keep sniffing the aroma indefinitely or something equally stupid.
Just like GRRM's "gardening" concept, It's a fun anecdote to share to show how mysterious and "not like other writers" you are, to make fans go "wow how deep and insightful" but in practice it's:
1. Just an excuse to avoid actually writing your story well.
2. A recipe for disaster as shown by the track records of both guys.
Bringing up GRRM also reminds me that Isayama shat on GOT's ending with that "orz" tweet and now he might've botched his own series even worse

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