So here, we have Tazkol as a Black Lantern, powered by the Black Light of Death. Now with the help of the Green Lantern Wiki, here's some context.

The Black Lantern Corps consisted of various slain and deceased beings throughout the universe who fell into the domain of the dead. There, they were used by the Lord of the Unliving, Nekron as part of a plan to wage a war against the Emotional Spectrum. The Blackest Night Prophecy spoken by Qull of the Five Inversions foretold of The Blackest Night where the enemies of the Guardians of the Universe would rise up against them and destroy their great work. Their goal is to steal the hearts of the living while swelling the ranks of the dead, all as part of a plan to bring back their true master who will make the cosmos devoid of all life.

Powers of the black lantern rings include: reanimation of corpses, healing/regeneration(at least to a point proportionately to the damaged corpse upon getting a ring), Energy Spectrum Assimilation, and an infectious attack that can turn victims into black lanterns.

Emotional Spectrum Project(Links)
Black(Death)-http://www.furaffinity.net/view/11411296/
Red(Rage)-http://www.furaffinity.net/view/11203788/
Orange(Avarice)-http://www.furaffinity.net/view/11210862/
Yellow(Fear)-http://www.furaffinity.net/view/11225704/
Green(Will)-http://www.furaffinity.net/view/11300784/
Green Alpha(Will)-http://www.furaffinity.net/view/11418549/
Blue(Hope)-http://www.furaffinity.net/view/11237639/
Indigo(Compassion)-http://www.furaffinity.net/view/11220743/
Violet(Love)-http://www.furaffinity.net/view/11181430/
White(Life)-http://www.furaffinity.net/view/11411394/