This is an analysis of the Tragic Qualities of Book XVI: The Death of Patroclus:
Patroclus is the main protagonist. We are sympathetic to him as he's intrinsically good, as shown by his tending to Eurypulus' wound; his actions in battle are considered standard in Greek warfare. His efforts in battle are ultimately fultile however as his fate had already been prophesied, creating sense of wastefullness and futiliy. Crucially Patroclus' death is the his fault as Homer says 'had he heeded Achilles' he would have lived, his self-delusion led him to challenge the God Apollo, the fourth attempt being his downfall. There is a rising sense of doom throughout the Book as Homer's language gets increasingly extreme and Patroclus more overconfident. Emotively Patroclus gets enlighted at his very end, turning the dramatic irony of his predermined death to pathos, to prophesy Hector's at the hands of Achilles. Homer demonstrates a subtle Greek biase as Patroclus, attendant of Achilles, had to be 'stripped of his armour' by the Gods for the 'best of the Trojans' to prevail.
This is a mind-map of quotes from the Iliad supporting my argument above that Books 11-16 [particularly 16] are a Tragedy in minature. As you can see the sections are colour-coded, the darker ones being quotes from the narator Homer, the lighter Homer through another character [in this: Achilles, Patroclus or Hector].
When analysing this book it's useful to consider the common characteristics of tragic heroes according to Aristotle in his book on literary theory titled Poetics:
1.Member of the nobility - ancestors are kings/queens/nobles probably is one himself
2.Is pre-eminently great, usually innately kind, but has a 'hamartia' ('tragic flaw' leading to his own downfall)