Nekron is the physical embodiment for the Black Lantern Corps which are powered by death.

He is revived as a member of the Black Lantern Corps.

Both sides are later seen reunited as members of the Black Lantern Corps.

Recently revived as a member of the Black Lantern Corps.

Revived as a member of the Black Lantern Corps.

His body was later revived as part of the Black Lantern Corps.

Indigo says that the Lantern Corps must unite to defeat the Black one.

Sayd says the future of the Lantern Corps must be discussed.

He later participates in the final battle against the Black Lantern Corps.

By many accounts, the ring is also effective against yellow, contradicting an age-old weakness of the Lantern Corps.