The United Nations Conclave, usually shortened to just the Conclave, is a recurring organization in the Guilty Gear series. A group composed of four sages, they act as the supreme advisers to the United Nations and, politically, they eclipse even the Sanctus Populi.
Each sage appears to wear metallic skull-like masks that bear Roman Numerals on them along with a trench-coat.
According to Zato-1, they were responsible for hiring the Assassin's Guild to prevent Dr. Baldhead using a certain untested medical technique to save his patient, as it was crucial to their World Rebirth plan. The Senate is also responsible for taking Zato's body away shortly after his death.
After the ending of the Crusades, the United Nations had to establish control over the leftover land, where The Senate got involved. They were the ones responsible for setting up Ky Kiske as the king of the Allied Kingdom of Illyria by using the information that he has been in a relationship with a gear as a method of strong-arming.
During Sol Badguy and Sin Kiske's journey to find one of the Sacred Treasures possessed by the Conclave, they start taking action against them by increasing the bounty on Sol's head, attracting numerous bounty hunters. During the night, they send out a massive gear-like beast after the two, but it yielded no results.
When Sol and Sin actually enter the facility where the weapon is being supposed to be held, they are met with an ambush from a specialized soldier unit which acts directly under the orders of the Senate. Shortly afterwards, they are attacked by Baldias, who has been defeated by Sol, and has been missing ever since.
The Conclave has recently used Dr. Baldhead's technique to revive Zato-1 for both the purpose of researching the Forbidden Beast technology and to develop and perfect the art of resurrection. Ky Kiske seems to possess a decent amount of intelligence on them, but according to Ramlethal Valentine, his understanding of the World Rebirth operation is incomplete. According to I-No, That Man has been seeking information on the on-going events, but with no results.
They have been addressing their current actions amongst themselves as the "world conquest" and "shaping the world as [they] desire", while also being referred to as World Rebirth. Their means to do so far are gaining access to the Backyard, allying themselves with Ramlethal Valentine (and possibly by extension, with the Merciless Apocalypse itself), and manipulating the majority of the cast to do their will. The Conclave also has control of a device known as the Cradle, which houses the body of Justice whom they seek to revive by binding a soul to her.
In Guilty Gear Xrd's Story Mode, it is revealed that this organization has been manipulated by the Sanctus Maximus Populi leader, Ariels, into executing her own objectives.
Chronus, the sole survivor, is interrogated by Faust about the Japanese and seemed ready die to atone his sins, as he feels guilty for not only wrecking Faust's reputation when he was Baldhead by hiring the Assassin's Guild to do what they did to the doctor's young patient, but also for the previous events he had done. However, Faust had no interest in killing him and kept asking Chronus on the Colony’s true agenda. Chronus reveals he has no secret motives behind what the Colony wants with the Japanese, nor what medicine they give them. This leads Faust to believe there is a high power greater than the Conclave.
They have the absolute power in terms of right in speaking, having the absolute word and influence in matters of international government and economics.