

In response, Renathal had Mal'Ganis imprisoned and in a conversation with the Maw Walker, admitted that if Kael was farther along in his penance, the prince would consider him as a new Harvester of Envy or Dread. They were subsequently joined by Renathal, wearing the Crown of the Harvesters, and learned that Mal'Ganis and his cohorts had been a ruse in order to allow for the successful rescue of Sire Denathrius. However, after the Maw Walker killed Gorgannon and Diathorus the Seeker, Mal'Ganis entered the fray, and Kael, alongside The Curator and The Stonewright, aided in the fight by stunning Mal'Ganis with beams of anima. When the Maw Walker located and challenged Mal'Ganis to reclaim the medallion, Kael'thas fought against Lady Kivretan. Though the trio was able to track and down and kill Nal'ragas, the latter had already given the medallion to Mal'Ganis. As the mission progressed, Kael couldn't help but express regret at having allied with the nathrezim in life. Vashj merely pointed that Kael was assuming that Illidan was dead and mortal, things that she wasn't sure were true. During their mission, Kael commented on how Illidan would have relished this and questioned Vashj as to what fate was chosen for him. Kael, Vashj, and the Maw Walker then joined forces in hunting them down and recovering the Medallion of Wrath from Nal'ragas, while uncovering hidden nathrezim. After the Stonewright revealed that Chelra the Bladewall had been a nathrezim, Kael was stunned and remarked that he had grown too trusting in his penance. In response, she informed him that she also had no shortage of victories and questioned if he could say the same. As the group joined Renathal's entourage and headed towards the Stonewright, Kael'thas questioned Vashj as to why she was sent to Maldraxxus when she had no shortage of sins herself. As they departed, Vashj reminded Kael that they were there to hunt the dreadlords and told him not to join them this time. In time, Kael'thas was reunited with Lady Vashj when she and the Maw Walker were sent to Revendreth by the Primus in order to deliver missives to Prince Renathal and The Stonewright. Kael'thas accompanied the covenant forces that invaded the realm of Korthia and occasionally appears as a visitor in Keeper's Respite. Though Kael'thas' fury had not abated, he began to accept his own responsibility for failing his people. Kael'thas was part of the combined Venthyr and Necrolord forces that confronted Kel'Thuzad, but the archlich escaped to the Maw. Upon learning that Kel'Thuzad was not only in Maldraxxus but also partially responsible for the troubles of Revendreth, in combination with his being unburdened of the sins of others, he was filled with anger and swore vengeance for Quel'Thalas.

The Accuser chose to personally oversee Kael'thas' redemption, cleansing him of his excess sins with the help of the Maw Walker. This corruption to his sinstone made Kael'thas' soul very strong, but also very unstable, self-destructive, and pushed to the limit of its existence, rendering him a weapon that must either be redeemed or would be cast into the Maw. However, Sire Denathrius took him to Pride's Prison within Castle Nathria not to redeem his sins but to amplify them, burdening Kael'thas with the sins of others through experiments and filling him with immense anima and sins beyond what he already carried. Upon his death, Kael'thas was assigned by the Arbiter to Revendreth within the Shadowlands.
