S1·E54 The Return of Doctor Dark

Ming sets out to rule the entire universe by stealing the first of the three shards of the Orb of Konos from the Yucatan rain forest. At Monitor, Mandrake picks up telepathic signals from Mara, prompting Rick's journey to the Well of Essence, where he finds her in a cocoon. Dr. Dark locates the second shard with Ming, but in a confrontation between the two the evil ex-shadow lord drains the crystal's power, capturing it in his own body. Flash and Mandrake travel to a frozen planet to recover the third shard, only to discover that Ming has beat them to it. Back at Monitor Mara emerges from her cocoon, now a shadow lord. The Defenders rush to the Amber Keep on Rylos --the only place where the Orb of Konos can be reassembled- to discover that Dr. Dark has double crossed Ming and entered the Shadow Void to become the supreme ruler of the universe. Mara enters Dr. Dark's mind and prevents him from regaining control, thereby allowing the Orb to take back the power he stole from it, and destroying the evil warlock in the process. The Defenders escape the planet and Mara stays to become the new shadow master, ensuring that no one ever again splits the Orb of Konos.