Iden
Iden was one of the intelligent holograms created by Hirogen engineer Donik to serve as prey for their holographic training simulations. He was modeled after a member of the Bajoran Militia (though his uniform had no rank insignia). As a result, he believed in the Prophets as gods, like many biological Bajorans.
As one of Donik's creations, Iden could learn and improve his abilities with each hunt, and was the favorite prey of his Alpha. After repeated violent "deaths" at his Alpha's hands, Iden killed him. He stole a ship and liberated the other holograms on their space station. Using this ship, Iden attacked and liberated more stations, resulting in heavy Hirogen casualties.
One such liberation drew the attention of the USS Voyager when Donik sent out a distress signal. A Hirogen ship arrived shortly afterwards and insisted the holograms be destroyed. As Voyager gave chase, Iden ordered The Doctor be "liberated" from them, and his program was transferred to Iden's ship. Iden required The Doctor's help in repairing malfunctions in some of the other holograms.
Iden had a vision of a new homeworld for holograms, a place biological lifeforms could not hurt them. He chose a class Y planet, uninhabitable by humanoid lifeforms, and named it Ha'Dara. However, he required assistance in finishing a photonic field generator that could sustain the holograms he had freed. He was successful in convincing The Doctor to help him. Captain Janeway refused to provide help, so The Doctor transported himself to Iden's ship. Iden then kidnapped B'Elanna Torres to finish the generator.
Initially, Iden seemed reasonable, but eventually developed a messiah complex. He believed, in addition to forming their own unique culture, the holograms should form a new religion and offered to deify The Doctor as the "Great Healer" and "Father of us all" and an object of worship. He attacked and destroyed a Nuu'Bari mining vessel, taking three holograms from them. When those holograms were discovered to be mindless tools, capable of only basic tasks, he accused B'Elanna of displaying her prejudices when she affirmed that it was impossible to upgrade the holograms to achieve greater intellectual potential.
When his ship reached Ha'Dara, pursued by the Hirogen and Voyager, Iden transported the unarmed Hirogen crew to the surface with the intention of killing them. B'Elanna disabled the generator, but Iden had transferred himself to The Doctor's mobile emitter. The Doctor found and shot Iden after he refused to surrender. The blast destabilized Iden's program and rendered it unrecoverable, effectively "killing" him.
The leadership of Iden's people was taken over by Kejal after his deactivation. She and Donik hoped to alter the other holograms to prevent further bloodshed in the future. (VOY: "Flesh and Blood")