- Alternative Character Interpretation: The scene where Naphi tries to follow Mocker-Jack down a sinkhole. Many people see it as simply a sign of her insanity, believing she could kill a giant mole—that is currently on fire—with a knife. However, if you think about it, it isn't entirely unlikely that the captain was knowingly trying to off herself; after all, she was pretty obviously derailed by the mutiny earlier, and now she's just watched her philosophy get murdered by something that was not her.
- Does This Remind You of Anything?: At one point, Caldera talks about the "trainsfolk down south" that get regularly labelled as pirates, while all they want is to protect their coasts from waste-dumping corporate trains.
- Vague Age: Most of the characters, but most confusingly, Captain Naphi. Initially her grey hair could be seen as an indicator of her age, however since other characters who are supposedly around the same age are described as having red or black hair, and some people are described as having unnatural hair and skin colors naturally, Naphi could very well be in her twenties or thirties. Since she's based on Captain Ahab of Moby-Dick (who was canonically fifty-eight), it seems safe to assume she's middle-aged—but there are several areas in which her character is vastly different from Ahab, so she could still be far older or younger; and we have no idea what the average lifespan is in this version of the future, so for all we know, Naphi could be several centuries old.
- Cool Old Lady: If we assume she's fifty-eight or older, and if we're counting fifty-eight as 'old.'
- Shoot the Shaggy Dog: From Sham's perspective, the story is harsh and the ending is bittersweet. From the Shroakes' perspective, the story is harsh and the ending is actually pretty upbeat. But from Captain Naphi's perspective, it's a massive Tear Jerker with a heart-wrenching Downer Ending. Subverted in that she doesn't die, but some might say her ultimate fate is actually worse.