Kara meets a prisoner named Brackus after she is spirited to the Dark Realm. Brackus tricks Kara into believing that he is a friend and will help her escape.

After Doku poisons Seth, the Defenders put their trust in Brackus to help find the mysterious healer.

The Defenders face a powerful guardian.

Rion has a dream that he fails to stop Malco from destroying the realm. It is revealed that Rion is half Ethos and that he is the only one that can destroy the Ethos within Malco and save Rados.

Rion, Brackus and Erik meet up with Mel and Seth at Rivas island to look for Brim, the stonecutter.

Mel see the temple of Yan-Sumos, where the Wizards of Yan also face the Ethos.

Flinch convinces the Zads to work with the Ethos; Brackus shares about Malco's intention of using the orb of Ogama-Yan to look for the parts of “The Celestial Abyss”.

Zads break into Gata-Shin prison and capture Si'i. The Defenders attempt to rescue Si'i, leaving Rion behind.

Mel discovers that one of the pieces of the Celestial Abyss is at the Temple of Yan-Mara.

When the Defenders set out to find the second icon, they encounter competition from the wizard, Kor who has been resurrected by Malco. Mel discovers she is the only one with the power to free Kor from Malco's hold.

After almost causing the destruction of Arboth, Seth decides to leave the other Defenders. When Rion learns of Seth's whereabouts, he sets out to find him. Mel, Erik, and Adam are shocked when Kara returns with The Orb.

Adam and Erik rescue an innocent Maiden, only to find she isn't quite the victim she seemed. Mel is kidnapped by Lady K'Tahsh and learns she is to be sacrificed for a mysterious purpose.

Mel escapes Lady K'tahsh but the Ethos have captured Si'I, a monstrously powerful guardian. Back at the Dojo Seth becomes suspicious of Kara and traps her, only to discover she is the shapeshifter Kali.

To rescue Kara from the Mortagarian's underwater realm, the Defenders must steal the Tome of Al Mortagar (an ancient book that holds the secret to the original Sigils of power) and exchange it for Kara's freedom.

Erik goes searching for a temple to resurrect Kara only to discover that he must complete three dangerous tasks to get what he wants. The other Defenders decide that Malco is to blame for the loss of Kara.

The Defenders enter the Spell Zone looking for the fifth icon. They are captured by a doomsday cult, and discover that the leader plans to use them as a sacrifice! Brackus is betrayed by Lady K.

With the Dojo under siege by the army of Sigil Slayers, the Mortagarians arrive and join forces with the Defenders to beat back Lady K'Tahsh and the Sigil slayers. Rion has been overtaken by the Ethos inside him.