This is the page for the 3rd Harlequin in DC Comics continuity.
A so-far-unnamed young woman who appeared in Green Lantern Corps Quarterly.
The origins and motivations of the woman known only as Harlequin are unknown, though she claims to have discovered she had the ability to induce hallucinations in the minds of other at an early age. She first appeared when she attacked Alan Scott, the original Green Lantern, with whom she appeared to be obsessed (she had somehow learned of his relationship with Molly Maynne, the original Harlequin, and had decided that she was destined to be Maynne's successor and be with Scott). She created illusions of Scott's former foes Solomon Grundy and Icicle to challenge him before appearing to him herself, at a time when Scott had regained his lost youth (he at first believed this to be one of Harlequin's illusions, but it proved to be unconnected to her).
She later attacked Maynne, now Scott's wife, at which point he lost his temper and showed her a vision of himself as a lord of Hell with her as his slave. The Harlequin fled, declaring that Scott had 'ruined everything', but later resurfaced as one of the villains summoned by Neron to wage war on Earth's heroes, and apparently appeared to Scott in a dream. She has not been seen since.
She appears briefly in Underworld Unleashed #1 as one of the many super-villains that take Neron up on his offer.
Her primary tool was her glasses which projected realistic three-dimensional holograms and fired energy blasts.
Her secondary tool is a mandolin with an extending handle which she uses as a defensive weapon (especially against the Golden Age Green Lantern due to his weakness to its wooden construction).