The Veil was a DC/Justice League supervillain who first appeared in 1989's Animal Man #7, being a minor antagonist towards the titular Justice League member.
No backstory or history is recorded of this criminal, but what is known is that he is a robber with a hate for the Animal Man and an alliance with the Red Mask. Though his powers included manipulation over darkness and abilities to phase through solid surfaces, his very faculties led to uncontrollable strange visions that got so bad that he went completely insane and clawed his own eyes out before being sent to Arkham Asylum.
The Veil was a secret criminal organization led by a mysterious armored individual known as Pylon. The purpose behind the Veil was to seek out, target and eliminate extraterrestrial threats to the planet Earth. Pylon learned about a new group of young heroes calling themselves the Teen Titans and discovered that they were genetically bred alien/human hybrids, created by the race known as the H'San Natall.
The first of the H'San Natall's sleeper agents that they discovered was the primitive alien known as Fringe. While tracking Fringe through the forests outside of Leesburg, the Veil agents ran afoul of Leesburg's resident super-hero, Supergirl. Armed with hi-tech weaponry, they were able to capture both Supergirl and Fringe. They took them back to their lair where they were suspended from a device that negated their powers.
All of the H'San Natall's experimental subjects shared a psychic link with one another and it wasn't long before the Teen Titans learned of Fringe and that he was in trouble. The Titans, accompanied by Captain Marvel, Jr., Nightwing and Robin tracked the Veil down and fought them at their headquarters. The heroes succeeded in rescuing Supergirl and Fringe, but Pylon and his masked agents escaped.
A few weeks later, the Titans returned to the Veil compound only to find that it was abandoned. Their presence activated a self-destruct program that destroyed the building, but the Titans managed to escape.
Pylon then hired a mercenary outfit known as Dark Nemesis to bait the Titans into a trap so that they could study their powers. This plan too proved to be a failure, but the Veil did succeed in acquiring comprehensive biological data on all the Titans members.
The Veil returned when they discovered that the Teen Titans were having a recruitment drive on the top of a Metropolis night club called the Stain. Although they had compiled dossiers on the known team members, they did not have adequate information concerning all of the potential recruits, not to mention the Atom's power upgrades which he developed during the "Genesis" event. The battle turned into a massive superhuman free-for-all, but ultimately the Veil was forced to retreat.