This passage sees the entrance of Mezentius to battle, at the promptings of Jupiter, and the replacement of Turnus whose fate will be determined another day. In general terms, I think it is interesting to recognize the idea of fate in this passage as it is shows its face directly in line 740, as Mezentius about to slay Orodes puts his faith in fate and his destiny is in the hands of the "Father of the Gods and the King of men", intriguing and somewhat ironic as Vergil condemns Mezentius in 7.648 as a "contemptor divum". This fateful passage truly illustrates Vergil's use of Mezentius as a forerunner to the destiny of Turnus as he must meet and fall before Aeneas. .
As a particularly poignant moment in the poem Vergil employs Homeric allusion for the sake of adding striking detail to the scene. The first line uses a chiastic arrangement in "densos alacer Mezentius hostis"; Vergil depicts Mezentius with no less that the raging fury associated with Turnus. The word "alacer" brings to the surface a shining example of epic characterization, the epithet, mainly memorable because Vergil employs the same terminology to Turnus in book 12 line 337 thus establishing a forceful link between the two again pointing to Mezentius prefiguring Turnus" destiny as he will meet Aeneas in battle and will fall. Further to both themes is Acron's depiction as "infelix" again an epic epithet and once more it suggests that luck is a major factor in the episode.
Moving away from the idea of fate, Connington suggests a reference to the Homeric phrase"gaia melaina" with "atra humum", whether intentional or not this is the forerunner to many Graecism's and Homeric references in this passage. Other examples include the Greek accusative "paeana" perhaps picking up Achilles speech to the Greeks after the death of Hector in Iliad 22.365 a particularly apt epic reference in this instance. Further to this is Vergil's probable adaptation of Homer's sleep of bronze (Iliad 11.
