Pyrrhus. The rugged Pyrrhus – hero to the Greeks – villain to the Trojans. Also known as Neoptolomus. Here, clearly the villain – he is hellish, like a beast, dreaded etc.
Hamlet is interested in the Trojan perspective, it occurs to me now. In Greek stories, Pyrrhus/Neoptolomus is portrayed as a compassionate boy, who, when he kills Polyxena, kills her the nicest way possible. (Oh those Greeks, they love a good lady sacrifice!)
Here, Pyrrhus is worse than a devil but he is also the center of the story, prowling the streets in search of reverent Priam.
And perhaps we’re meant to associate Priam with the other king father in this play, the one that was also killed by a villain. I see now why Hamlet wants to hear this speech.