Boundlings

"Rods of steel run through the Boundling's inflamed, swollen flesh. Its body had warped to fit its cage; even its red eyes are distorted, pulled out of alignment by the band across its face."

Boundlings are unfortunate fish bound by metal cages and rods, similar in construction to the devices that torment Bound-Sharks. Their bodies are so distorted that it's unclear what type of fish they were originally, but they seem to resemble extremely large, warped tuna.

Who Would Do This To A Fish?

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As with the Bound-sharks, the imprisonment of the Boundlings is most likely the work of the New Sequence, in an operation headquartered at the Grand Geode. and also manage a shark-nursery there. It is unknown precisely why they so torment the poor fish, but as with Bound-sharks it may have to do with inducing a feeling of pathos or otherwise increasing a Sequencer's vulnerability to the Dawn Machine.