15 DEADLIEST Comic Book Assassins

Slade Wilson took part in a military experiment, which allowed him to access 90% of his brain at once. Taking on the name Deathstroke the Terminator, Slade became a world-class mercenary.

Deathstroke is such a deadly strategist and fighter, the Teen Titan's arch-nemesis battled the entire Justice League, simply by relying on superior tactics rather than brute strength. The one-eyed assassin's armour is laced with promethium, Nth metal, and a gravity sheath, making it strong enough to withstand a punch from Superman. According to his associate, Wintergreen, Deathstroke has mastered a mediative technique that allows him to recover from almost any wound.

He has a knack for instilling fear in others, psyching them out in battle. He managed to do this to Green Lantern Corps member, John Stewart, even though Green Lanterns have a reputation for conquering fear.

Despite his skill, Deathstroke doesn't' get cocky and takes every job very seriously. In Deathstroke #4, it is shown that Slade checks every room he stays in for bugs and explosives before scrambling the phoneline so no one can listen in on his calls.

Basically, if Deathstroke is coming after you, you might as well accept your fate and kiss your loved ones goodbye.