What are examples of literary elements in act 5, scene 3, lines 55–90?

Literary elements in these lines of Julius Caesar include apostrophe, metaphor, and soliloquy.
When the two men find Cassius's body, they are shocked to find him dead. Titinius uses a metaphor, which is the direct comparison of unlike things for effect. He refers to Cassius as the "sun" and speaks of his death as a sunset, specifically comparing his "red blood" to its "red rays." He introduces this idea through apostrophe, which is direct address, often to an inanimate object or natural element: in this case, "O setting sun!" He continues the weather metaphor for the ill fortune or defeat of Rome that comes with Cassius's death; without the sun, there will be "clouds."
Messala also uses metaphor and apostrophe. He contrasts death and birth, comparing the error that has led to the death as a mother dies in childbirth. He speaks to error as to a child: "O error!"
After Messala leaves, Titinius speaks a soliloquy before he kills himself, a monologue when the character is alone on stage. (The dead body doesn't count.)
https://www.playshakespeare.com/julius-caesar/scenes/act-v-scene-3

There are a number of notable literary elements in this exchange between Messala and Titinius. For example, in lines 70-75, we see an extended metaphor with the use of figurative language personifying the "hateful error" that led to Cassius's "deed." Messala appeals to the error itself, "melancholy's child," describing it as having been "soon conceived" (a pun on the word "conceived," which can mean either conceived like a child or conceived as an idea) and then having killed "the mother that engender'd thee."
Later in the scene, Messala highlights a use of pun, declaring his intention to meet Brutus and "thrust" the news upon him—"I may say "thrusting" it / For piercing steel . . . shall be as welcome to Brutus as tidings of this sight." The structure of the sentence here privileges the imagery, and contains potential dramatic irony, an allusion to other instances of "thrusting" "piercing steel" in the play (notably relating to the death of Caesar).