Teen Titans and Batman. I feel like early career Deathstroke fought Batman and shifted his focus to the Titans later in life, particularly towards Robin, to hurt Batman.
Honestly, I would rather see Deathstroke go in conflict with characters outside the usual characters like maybe Mr. Terrific, Vixen, Justice Society, Katanna, John Henry Irons or Natasha Irons/Steel, or even Wonder Girl.
