Merlyn the Archer is a professional assassin that's an enemy of the DC superheroes, Batman, the Green Arrow, and Booster Gold. He was a former member of the 1000, but currently a member of the League of Assassins.
Arthur King was a professional Archer. Oliver Queen was inspired to take up archery all because of the skilled archer, Merlyn "the Magician." Once Green Arrow was famous, Merlyn challenged the Green Arrow to a public archery contest. Merlyn manage to defeat the Green Arrow, and disappeared with the victory under his belt. Merlyn later reappeared and became a member of the League of Assassins, and a former member of the 1000.
In the Live Action show Arrow a man named Tommy Merlyn appears in the first episode and is revealed to be an old friend of Oliver Queen and is dating Laurel Lance. His father is Malcolm Merlyn is business man and played a part in Oliver's father's death and Oliver's shipwreck. He also has special archer training and has a hooded costume. Malcolm is played by John Barrowman and Tommy is played by Colin Donnell.
In the Green Arrow DC Nation Showcase Merlyn appears where he is hired by Count Vertigo is assassinate Princess Perdita in an airport, but is stopped by Green Arrow. In this show he is voiced by Malcolm McDowell.
In the video game, Injustice: Gods Among Us, Merlyn appears in one of the Green Arrow S.T.A.R. Labs missions imitating Green Arrow. Green Arrow must hit Merlyn with three arrows in order to accomplish his mission