Leader of the pack

Though many of the Changelings had accepted Thorax, several of them continued to cling to the old ways, and Thorax struggled to bring them around. He was thus thrilled when Spike invited him to visit Ponyville, hoping that his Dragon friend could give him some helpful advice. Unfortunately, Spike had accidentally invited Thorax to visit the same day he had invited Dragon Lord Ember, and Spike feared that the two rulers would clash and spark a Changeling-Dragon war. As such, he and his pony friends kept trying to keep the pair occupied and away from each other, inadvertently upsetting both in the process. When an angry Ember expressed her frustration with Spike, Thorax believed she was attacking him and transformed into a bear to confront her, only for the truth to come out as Spike panicked over the encounter.

Thorax and Ember both left in disgust, only to run into each other at a nearby lake, where Thorax opened up about his problems to Ember. She encouraged him to own his authority as the Changeling leader, and Thorax then helped her realize that she could be sensitive to the feelings of other and express her own without it being awkward. The two then returned to address Spike, whom they forgave after expressing their displeasure with his actions; both were then honored at a welcome ceremony initially intended for Ember alone. With Ember's help-which he continued to receive through correspondence with her-Thorax soon had all the renegade Changelings convinced but one: his brother Pharynx.

Starlight and Trixie soon arrived at the hive for a surprise visit, and became acquainted with the situation with Pharynx after he took them prisoner and brought them before Thorax. While he eagerly shared the changes in the hive with his friends, Pharynx caused continual problems with his behavior. The other Changelings, Starlight, and Trixie soon felt that it might be best to exile Pharynx, but Thorax refused to give up on the brother who had defended him in their youth. He was soon forced to deal with Starlight's efforts to help Pharynx by joining his brother in dealing with a Maulwurf that had been plaguing the hive recently. After the rest of the hive joined in and expressed their regret at wanting him to leave, Pharynx was able to embrace his own love for the hive, and transformed to join his people.