It seems Hollywood can’t come up with anything original anymore and comics aren’t immune to retreading old material either. Here is a list of comic characters that are basically the same person.
Deadpool vs Deathstoke
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DC’s Deastroke debuted in 1980 as an enemy for the Teen Titans. He is an assassin and mercenary. He is a tactical genius, expert marksman, swordsman, and hand-to-hand combatant. A serum also granted him super-strength, speed, agility and durability. He also has accelerated healing though not to levels where he could regenerate limbs or organs.
Marvel’s Deadpool debuted in 1991 as the fourth wall-breaking ‘Merc with a Mouth’. Originally cast as a villain to foil for Cable and the New Mutants, since then he has morphed into an anti-hero. Due to his similarities to DC’s Deathstoke, his creators gave him the name Wade Wilson as a play off of Deathstroke’s real name, Slade Wilson. Deadpool’s abilities include an accelerated healing factor as well as being an expert martial artist, marksman, and swordsman.