YMMV / Tunnels

• Audience-Alienating Ending: The finale turned a lot of people off the series, due to its combination of Esoteric Happy Ending, Gainax Ending, and Sequel Hook. Chester and Drake, two series regulars, die largely meaningless deaths (and so do Rebecca 2 and The Old Styx, who were the main antagonist of the series alongside Rebecca 1, and are sort of put aside by the armagi plot...which also gets killed pretty fast). Elliot saves the world from the Styx, but then accidentally destroys most of it herself. Will might be transforming into a Styx. Earth is revealed to be an ancient spaceship, which leaves the solar system for places unknown (which does not fit the tone of the series, and comes way too late to be of any genuine relevance, given the series ends right up there).
• Broken Base: The series's finale. To some, it is the adequate culmination of a surprisingly well-written Mind Screw series of books, while to other, it is a bizarre and disturbing ending which does not end things very much, feels quite disjointed of the rest of the series, and ji a mix of Ass Pulls, Deus Ex Machina, and many characters getting a bridge dropped on them, aside of not being (as already mentioned) conclusive at all.
• Crazy Is Cool: Martha varies between this, and just plain crazy.
• Esoteric Happy Ending: Some feel the ending of the series is this. The Styx plan is stopped and humanity survives. However, in the process, Earth is removed from its orbit around the sun. Humans might survive underground, but all life on Earth’s surface will die out as the surface freezes over.
• Too Bleak, Stopped Caring: Perhaps inevitable, given the sheer amount of characters who die or reveal themselves as traitors.
• What Do You Mean, It's for Kids?: Yeah, it's for kids, and also is full of claustrophobic perils, biologic horrors and bloody deaths.

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