“There is no war so hateful to the gods as a war between kin,” a wise character observes in the second season of HBO’s House of the Dragon. “And no war so bloody as a war between dragons.” Sadly, by the time those words are uttered, both kinds of war have come to seem inevitable. King Viserys I Targaryen (Paddy Considine) is dead, and his bratty son Aegon (Ty Tennant) has usurped an Iron Throne that rightfully belonged to his older half-sister, Rhaenyra (Emma D’Arcy). Season 1 ended with the spilling of first blood...