In Post Crisis continuity, Crazy Quilt was a talented painter, who led a double life as a criminal mastermind. He committed his crimes using paintings to leave clues, until he was betrayed by his lackeys. Later, he was blinded by a gunshot, and then sent to prison. While behind bars he volunteered for an experimental procedure, which restored his lost vision by a unique helmet fused to his optics nerves. While the operation itself was a success, he can only see the world in blinding vivid colors, which drove him insane. He has clashed with Gotham's Batfamily repeatedly with multiple wacky and eccentric schemes involving colors as a gimmick.
No longer able to take the blinding colors, he kidnaps a surgeon to restore his sight, leading to a confrontation with Batman and Robin. During the battle, Robin deflects Crazy Quilts color beam back towards him, permanently blinding him. This drives Crazy Quilt to hating Robin, at one point leading him almost fatally beating a inexperienced Jason Todd to death, believing him to be Dick Grayson, who had left the Robin role.
Crazy Quilt spends time in Belle Reeve when he is captured, taking part in a large prison riot, while under Hector Hammond's psychic control. Shortly after this Crazy Quilt joins the Secret Society of Super Villians and is one of the many members taken down in a sting operation where Martian Manhunter disguised himself as one of their members and led the JLA to their secret location.
In the N52, Dekker was retconned into being a former top scientist at Wayne Enterprises as one third of the "Doctors Three" which was a trio of Gotham's most intelligent scientists and researchers. However, his obsession with immortality and his maniacal work on Dionesium: a liquid that could restore the dead and heal the living to their prime states of health: would lead him to be cut off from his job. He would later go crazy and become his Post Crisis counterpart by name. When Joker revived himself using the substance using a secret pool under Gotham itself, Batman would go to Dekker for answers, and, in a panicked state, he would inject himself with a experimental formula of Dionesium, which turned him into a rotting zombie in seconds, killing him.
A successor to Quilt would appear in Rebirth storylines in cameo roles looking much like Dekker himself in his Post Crisis attire, but it has not been disclosed if this is the case or if it is someone else entirely. If so, it likely makes his N52 history obsolete as it doesn't match that version of the character in terms of continuality.
Powers and Abilities
Crazy Quilt uses a special helmet that allows him to hypnotize his victims with blinding colors, as well as shoot fatal laser blasts, and blindingly bright lights after it was upgraded by a mechanic that Quilt later killed after he asked for his cut of the funds Quilt had. It can also act as a pair of extra eyes for Quilt himself, allowing him to see what's happening behind him by flipping his helmet around.
In Other Media
He has appeared several times in Batman: The Brave and the Bold. the first time he attempts to steal a painting but is foiled by Batman. His next appearance is in "The Color of Revenge" in which he is blinded by Dick Grayson. He tries to get revenge but is defeated by the Dynamic Duo. In his second appearance his themed henchmen the Color Guard are a throwback to the Adam West series.