In our current read, Sand of the Arena, the Ethiopian venator Lindani spectacularly saves the lives of the proconsul’s family in the arena at Londinium, after an antelope buck crashes into the audience.
[As it so happens, Mary Beard today reports on a field trip with her Roman Britain class to London and links to a nice page of the London amphitheatre.]
The venatio (hunt) was a popular spectacle during gladiatorial games, usually as a warm-up to the main event. The trained hunter, like our Lindani, was called venator, as opposed to the bestiarus, who was mainly animal fodder.
The Brooklyn College Classics Department has two nice pages on the subject, Venatio I and Venatio II (Illustrations). This is part of Roman Gladiatorial Games.
Smith's Dictionary of Greek and Roman Antiquities, John Murray, London, 1875 at LacusCurtius has an entry Venatio, but the text does not mention the term venator, only bestiarii.
It also says there that,
[these spectacles] were exhibited after the abolition of the shows of gladiators. There is a law of Honorius and Theodosius, providing for the safe convoy of beasts intended for the spectacles, and inflicting a penalty of •five pounds of gold upon any one who injured them (Cod. 11 tit. 44). They were exhibited at this period at the praetorian games, as we learn from Symmachus (Epist. IX.70, 71, 126, &c.). Wild beasts continued to be exhibited in the games at Constantinople as late as the time of Justinian (Procop. Hist. Arc. c. 9).
The above photo (right-click to enlarge, fully copyrighted) is the central piece of the Gladiator Mosaic in Bad Kreuznach, Germany. There are more depictions of venatores and bestiarii, and also one of beast on beast.
I'm in the process of rescanning those images as part of an overhaul and – long overdue – completion of my travelogues, as I have now much better equipment and software. However, I have to do it at odd moments.