What are some literary devices used in Hamlet, Act 1 Scene 5?

When the ghost of old King Hamlet charges his son to exact revenge on his killer, he calls Claudius, his brother and murderer, a "serpent," thus associating him via allusion with the sinful serpent in the Garden of Eden (1.5.45).  Not only is this an example of an allusion to the serpent in the Bible, but it is also a metaphor.

Further, he compares his former union with Gertrude, his wife, to a "celestial bed" and her new union, with Claudius, to "garbage" (1.5.64-65); this, too, is metaphor.  He also calls the poison Claudius used, "swift as quicksilver," employing a simile (1.5.76).  About Gertrude, again, old Hamlet charges his son to "Leave her to heaven / And to those thorns that in her bosom lodge / To prick and sting her" (1.5.93-95).  Thus, he compares the actions for which she will feel guilty to thorns via another metaphor.  There is no need for Hamlet to exact revenge on her because her guilt with accomplish it for him.