In Star Trek: Voyager #11, written by Laurie S. Sutton and drawn by Jesus Redondo, the ship is drawn into the Leviathan, an entity from beyond our galaxy who has brought species from across it to study. Beaming into a jungle-like habitat, the away team is besieged by Jem’Hadar, but these are very different. They do not talk and instead act primitive, wearing animal skins and using simple weapons.

Fans come to learn the horrifying truth: these are descendants of Jem’Hadar brought to Leviathan years before the Dominion modified them to be killing machines.

The Jem'Hadar, the Dominion's Storm Troopers, Explained
The Brutal Jem'Hadar Scares Everyone in the Alpha Quadrant

Although the Jem'Hadar debuted in the episode bearing their name, the Dominion was first mentioned a few months prior, in the episode "Rules of Acquistion."
Although the Federation has numerous enemies, few of them could compare to the Jem’Hadar. From birth, the Jem’Hadar undergo extreme mental and physical conditioning, to make them tools of oppression for the Founders. Every Jem’Hadar is unwaveringly loyal to the Founders and the Dominion, and would gladly throw their lives away for them. The Dominion ensures loyalty among the Jem’Hadar by hooking them to a highly addictive substance named Ketracel-White. If a Jem’Hadar goes without Ketracel-White for too long, they will die a horrible death.
The Dominion Made the Jem'Hadar What They Were--Against Their Will
The Vorta Were Also Victims of the Dominion's Manipulations.
Like the Jem’Hadar, the Vorta were not always docile slaves of the Dominion–they too were victims of the Founders' manipulations.
The Jem’Hadar were not the only species in the Gamma Quadrant the Founders genetically altered. The Vorta, who were introduced in the same episode as the Jem’Hadar, handle the administrative side of the Dominion. Most subjects of the Dominion do not interact with the Founders. Instead, the Vorta act as intermediaries. The Vorta are also cloned, and a person may interact with various iterations of a Vorta in their lifetime. Like the Jem’Hadar, the Vorta were not always docile slaves of the Dominion–they too were victims of the Founders' manipulations.
The Dominion Was a Dark Mirror of the Federation
Did the Dominion Genetically Alter Other Species As Well?


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During Star Trek: Deep Space Nine’s seven seasons, fans met just a few other species living under the yoke of the Dominion. In terms of physical space, the Dominion was just as large as the Federation, meaning many other races potentially lived there. If the Dominion genetically altered the Jem’Hadar and the Vorta for their own purposes, then it stands to reason they did the same with other Gamma Quadrant species, but fans just never saw them. The true extent of the Dominion’s evil may never be revealed.
What Ever Happened to the Jem'Hadar? Star Trek Needs to Reveal This Bit of Information
The Founders Must Liberate the Jem'Hadar and the Vorta

In the wake of the Dominion’s defeat, the fates of the Jem’Hadar and the Vorta remain unknown. In Deep Space Nine’s finale, Odo convinced the Founders to abandon their war and embrace a better way of living. No Star Trek show has checked in on the Dominion since Deep Space Nine went off the air. Picard’s third season featured a gaggle of rogue Changelings, but did not say if the Dominion had freed the Vorta and the Jem’Hadar. I hate what the Dominion did to the Jem’Hadar and freeing them would be the perfect way for the Founders to atone.