The Dark Acolytes - A very Secretive and Ancient Cult Order with an ominous design on controlling the minds and actions of mankind. Though the Titan Twelve are only now starting to come into their powers, the Twelve have the potential, even now, to block the Acolytes from accomplishing their stated goal.
The long term objective of the Dark Acolytes is to fully eliminate the Titans as a threat. However, in the short term, the Titans cannot be harmed physically, as they are under the protection of the immensely powerful Guardians until several months before the Titans began to approach their 21st birthdays.