The Black Mercy is a telepathic species. It reads the heart's desires and feeds the individuals a totally convincing simulation of it.
~ Mongul about the Black Mercy plants.

The Black Mercy is a telepathic and parastitic plant-like alien species. It was capable of attaching itself to a host, read the host's memories, then feed the host a totally convincing simulated reality that was based on the host's deepest personal desires. What the Black Mercy received in return for this state is unknown.



Ater Clemtia

This plant Ater Clemtia is also known as the Black Mercy.

The Black Mercy was a species of parasitic plant that were native to a world in Space Sector 2811. Its origin was traced to being the empathic offspring of the living planet known as Mother Mercy and was seeded by her upon maturity whereupon it was sent into the stars on a mission to alleviate the pain and suffering felt by the sick or by the dying.


At some point, the tyrant Mongul I discovered the home planet of the Black Mercy plant whereupon he began harvesting it for a more sinister purpose. Twisting the creature, he intended for the plant to be a killing tool and thus distorted their true original purpose by making it infect healthy hosts whereupon they slowly began destroying their victims. At the time of his harvest, Mother Mercy decided not to reveal her true nature and simply allowed the supervillain to continue upon his goal. He used the plant in his battles against Superman and the Justice League until he stopped coming as a result of his death. However, in time, his son came to the world and continued his father's usage of the Black Mercy plant. Mongul II later travelled to the planet Earth in order to accomplish his deceased father's wishes of conquering that world. With him, he brought a number of Black Mercy plant which infected animals and beings in a farm on the planet. Hal Jordan and Green Arrow after arriving in the field discovered a large number of Black Mercy plant which had infected the cows in the region. Mongul II ensured that the plant had plenty of water and "food" by allowing them to infest the native Humans in the region. During a fight with Mongul II, Hal Jordan attempted to burn the Black Mercy plant but during the skirmish both him and Green Arrow where infected by the creatures who made them live in a dream-like state.

Sinestro Corps

After the Sinestro Corps War, Mongul II discovered a Qwardian Power Ring whereupon he became a powerful member within the leaderless Sinestro Corps. Using his new power ring, he genetically altered a number of Black Mercy plant which transformed them from weaving dreams within its hosts to making them instilling great fear on their victims. Black Mercy was used against a number of members of the Green Lantern Corps which were investigating Mongul II's operations where it infected Sodam Yat and Arisia.

Powers and Abilities

  • Parasiticism : it had the capacity of feeding of the bioelectrical aura of a host organism until it died. It accomplished this feat by attaching to its prey with the main roots that consisted of needle-like vines which entered the skin of the host whereupon it fused with the nervous system. They left the host in a state of euphoria whereupon the plants slowly killed the host as it fed from the feelings generated by its victims.
    • Dream Worlds: after infecting a host and wrapping their tendrils onto them, the plant began altering the visual perceptions of its victim leaving them in a dream-like state where their fondest desires as well as wishes came true. This left them trapped within their own bodies which were in a near vegetative state whilst the plant began to slowly feed off their dreams until the hosts died.
    • Nightmares: when they were manipulated by a Qwardian Power Ring's fear energy which distorted their natural talents, the plant was changed with a new ability of making their hosts live in a nightmare state where their deepest as well as darkest fears came into reality. Victims latched onto by this brand of mercy suffer their most dreaded horrors untill they expire from the plants leeching effects.

Dream Worlds

The Black Mercy plant is capable of creating "dream worlds", each faux utopian realities that are a complete and utterly convincing simulation of the victims' deepest desires, be it wanting to be very rich and famous, longing for a family or becoming either a hero or a ruler. There are known victims whose "perfect worlds" are the taste of the psychic and parastitic powers of the Black Mercy.

  • Superman: in this simulated alternate reality, his father Jor-El's prediction was proven untrue. He is married to Loana, a beautiful Kryptonian woman who is a composite of Lois Lane and Lana Lang, and together they has two children including their son Van-El. In the midst of this, Krypton is going into politcal upheaval. His cousin Supergirl (who  in this version was not older than him; in current canon, shewould be almost 16 years older than him by that point) is attacked by anti-Phantom Zone protesters.
  • Batman: In this dream, young Bruce Wayne's parents' murder is foiled. He grows up and has a wife named Kathy Kane, and together they both have a daughter.
  • Mongul: In this nightmarish dream, Mongu himself kills the people he is fighting—Wonder Woman, Superman, Robin, and Batman—and goes on to conquer the entire cosmos.
  • Green Lantern: In this dream, Hal Jordan's father never died nor did his mother. Coast City was never destroyed. Sinestro never turned evil, and is his mentor and friend. They show the Green Lantern Corps fighting an unknown man possessed by Parallax. His family is together happy and he is dating his high school sweetheart Jen.
  • Green Arrow: in this dream, Ollie is married to Sandra Hawke and has a great relationship with his son Conner. He has at least 3 kids. His son Connor Hawke was Speedy or the equavilant of it. His identity is publicly known.


The worlds are temporary and people always break free. Either the plant loses its grip, or the people under its thrall may realize it is never their lives or life is never this perfect. It is possible it does not work because desires are empty.



  • Black Mercy Plant

    The Black Mercy plant in Justice League Unlimited

    The Black Mercy plant appears in the Justice League Unlimited episode "For The Man Who Has Everything", which is based on the Superman Annual volume 1 story of the same name.
  • In the DC Comics, the Black Mercy was used by Mongul as part of his revenge against Superman for ruining his chances to obtain War World. Following the Crisis on Infinite Earths, the Black Mercy plant was retconned to be a symbiotic species created by Mother Mercy, a sentient plant organism, and were intended to latch to terminally ill sentients and give them a happy, painless death. Mongul's son, Mongul the Lesser, later used several in a plan to kill his sister Mongal.
  • The Red Mercy

    The Red Mercy.

    In the Superboy comic books, there exists the Red Mercy,  a possible variation of the Black Mercy plant species. Unlike most typical and altered Black Mercy plants which grant their hosts a perfected dellussion or an unending horror show. These Red Mercies place the host in a what if scenario where events in their lives took a turn in the absolute worst direction imaginable, not simply taking an idnividuals worst fears and making them come alive. But putting them behind the drivers seat of the most ugly, despicable stances which the individual dreamers destiny could possibly take them.
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