* Oxymoron: "The Man He Killed" is an oxymoron, as it combines two seemingly contradictory terms: "man" and "killed."
* Personification: The poem personifies death as a "foe" that "wrestles" with the man he killed.
* Alliteration: The poem uses alliteration to create a sense of rhythm and flow. For example, the line "The foe of all of us" uses the alliterative sound of "f" to create a sense of urgency and foreboding.
* Assonance: The poem uses assonance to create a sense of musicality. For example, the line "He thought he'd 'list, as I did, for a spell" uses the assonant sound of "i" to create a sense of longing and regret.
These are just a few examples of the figures of speech used in "The Man He Killed." Hardy's use of these devices helps to create a poem that is both powerful and moving, and that conveys a strong sense of the tragedy and futility of war.