Bloodhound Lore Theories
Bloodhound: [Makes a quiet, upset noise]
Loba: You seem tense. Is something the matter?
Bloodhound: No. Nothing of importance. Let us press on.
This interaction between Loba and Bloodhound has a chance to play when the pair are in Energy Depot on Olympus.
We don't know what is affecting Bloodhound but I have a theory which actually makes a lot of sense.
The Theory
Bloodhound's parents worked at Energy Depot before moving to World's Edge. Bloodhound recognises it and it reminds them of their parents, causing them to make a silent noise of distress.
Bloodhound's parents were engineers who moved to the Epicenter at World's Edge (for their work) when Bloodhound was a very young child. It's entirely possible that they were from Olympus working on the Energy Depot project, and Bloodhound recognised it.
Some could argue that it's a fear of heights or a high-altitude breathing problem, both of which are considerable arguments, however the subtitles say that Bloodhound makes an "upset" sound suggesting distress i.e. PTSD.
