The Blue Lantern Corps is a fictional organization appearing in American comic books published by DC Comics, beginning in 2008 in Green Lantern vol. 4 #25 (January 2008) by Geoff Johns. Their powers, similar to those of other organizations based around the emotional spectrum, are fueled by the emotion of hope.
Fictional group history
The Blue Lantern Corps is one of the nine corps empowered by a specific color of the emotional spectrum within the DC Universe. They have begun to fill an increasingly important role within Green Lantern and Green Lantern Corps as major participants within the Blackest Night crossover event. First formed by the banished former-Guardians Ganthet and Sayd, they are based on the planet Odym (later Elpis) and their powers are fueled by the emotion hope.
The Blue Lantern Corps is rooted in the events that transpired during the Sinestro Corps War story line. During the first half of the event, Ganthet and Sayd serve as a dissenting voice among the Guardians as they acknowledge that the Blackest Night prophecy within the Book of Oa is coming to pass. Their willingness to embrace emotions and the love they have for one another leads to the two being banished from Oa. Two issues after their exile, Ganthet reveals the Blackest Night prophecy to the reader, Hal Jordan, Guy Gardner, John Stewart, and Kyle Rayner. In his description he says: "Elsewhere, a flicker of hope will shine from deep space, like a lighthouse warning the ships away from the rocks. The blue light will hold the line in spirit if not in strength". It is revealed at the end of the issue that Ganthet and Sayd have settled on a planet (later named as Odym), have created a blue power ring, and intend to form their own Corps.
Rage of the Red Lanterns
In the Rage of the Red Lanterns plot line, Ganthet and Sayd's Blue Lanterns are finally introduced. The Green Lantern Corps have just been ambushed by the Red Lantern Corps, kidnapping Sinestro from their custody. Hal Jordan, reeling from the effects of an attack from (newly added Red Lantern) Laira, finds himself being healed by the powers of Saint Walker. Saint Walker introduces himself to the Green Lanterns as the Blue Lantern of sector one. By being in his emotional proximity, Jordan's power levels are boosted as long as Walker hopes for his well being. Though Stewart is suspicious of Walker's intentions, Walker's ring creates an illusion based on Stewart's psyche, freeing him from the effects of the Red Lantern attack that caused it. With Stewart placated, Walker takes Jordan to Odym. There, the reader is introduced to the second member of the Blue Lantern Corps, as Walker and Jordan watch Warth being given a blue power ring by Ganthet and Sayd. After which the two former-Guardians ask Jordan to aid the Blue Lanterns in rescuing Sinestro from Atrocitus, as his survival is important in the upcoming War of Light.
Jordan reluctantly accepts Ganthet's request and goes with the Blue Lanterns to the Red Lantern home planet of Ysmault. Along the way, Walker tells Jordan that the Green Lanterns are nothing but a police force, and that Jordan would lead the Blue Lanterns like no other. Though Jordan tells him he has no intention of leaving his Corps, the reader observes Walker telling Warth that it was imperative that Jordan become a Blue Lantern. On Ysmault, Jordan locates Sinestro but is promptly ambushed by the Red Lanterns. He's captured by Atrocitus' forces, and though Atrocitus tells Laira that Jordan's flesh and blood belong to her, her attack is interrupted by the arrival of the Sinestro Corps. Chaos ensues, during which Walker and Warth come to Jordan's aid. They are shown not only boosting Jordan's power, but also capably handling the two battling Corps. Warth easily keeps the two from fighting one another, while Walker keeps Atrocitus himself at bay (though admittedly is unable to douse his red fire). During the conflict, Jordan seems to be able to appeal to Laira's true self despite the red power ring's control on her. Any true reversion of its effects are halted as Sinestro kills her. Outraged, Jordan attacks Sinestro and is so overcome with rage that Laira's red power ring chooses him as its new host. Atrocitus welcomes him to the Red Lantern Corps.