Trite to say but I wonder if the main “character” of Iliad’s book 12 is the wall of the Achaeans: the book starts with a discussion of its ultimate fate, its destruction by Poeseidon et al., the book ends with Hector bursting through its gates, not destroying but compromising the wall.
Another unusual theme of Iliad 12 is of thrown stones, which are twice evocatively described as falling like snow. Hector and Ajax are specifically described as throwing stones and it was they who threw stones at each other during their duel in book 7.
Like in book 7, the implication is that Ajax is stronger than Hector; for while both Hector and Ajax are described in the same language as throwing stones greater than a person of today could, we’re told Hector requires Zeus’ help to effect this. (Again we’re reminded that the first best of the Trojans is less than the second best of the Achaeans; meaning, the Trojans are doomed.)
.i`` * ^ / . . . . . ` `~ 