Our friends at Oobject have assembled 12 of the toughest examples of deep-sea diving suits around—from da Vinci’s cloth prototypes to the bell helmets made famous by countless Scooby-Doo villains.

Boniface has so far worn the suit in a series of trials in deep water pools - with a little encouragement in the form of sausages. Gorbunov, who is director of diving at Vladivostok Maritime ...