I liked both Worm and Pact, but was unimpressed by the endings. Both seemed similar in that the first 3/4 of the novel bring new information, the protagonist explores new options, etc., which keep it interested.
The remaining 1/4 of the novels are like putting almost everyone ever mentioned in the story, plus many new monsters, in the same room, and let them fight. About as interesting as a verbal transcription of 2 hours long Doom multiplayer.
Worm has too many fight scenes, that problem is not unique to the ending :-) I can't think of any big questions that were left unresolved, though.
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