Warning! Spoilers for Black Panther #19, by Ta-Nehisi Coates, Ryan Bodenheim, Michael Garland, and VC's Joe Sabino. on sale now.
Most often, the Marvel Universe gives the impression that symbiotes make everything better. When they're not causing Absolute Carnage, everyone from Eddie Brock and Spider-Man to Spider-Gwen and Deadpool have all found success during their times bonded with symbiotes.
While symbiotes have bonded with plenty of heroes and villains around the Marvel Universe, Black Panther has a grotesque, nightmare-inducing symbiote problem that Spider-Man definitely never had to deal with. The most dangerous of all of T'Challa's adversaries, Erik Killmonger, has returned, and this time, he's not alone... because he has bonded with a symbiote that's hauling his rotting corpse to T'Challa's door for some vengeance.
For the past few issues of the series, T'Challa was transported to an alternate reality where Wakanda utilized its advanced technology for the sake of conquest and expanded its empire to the stars. This empire was ruled by the vicious conqueror Emperor N'Jadaka, who stripped the other Wakanda's king of his memories, turning him into a slave. When a rebellion of ex-slaves -- the Maroons -- rescued and restored T'Challa to his former glory, Black Panther fought N'Jadaka and slew his adversary before returning home.
But N'Jadaka survived, thanks to the symbiote bonded to him. He pursued T'Challa to his Wakanda, forming alliances with multiple superpowered individuals within Wakanda in order to conquer this other universe's Wakanda. We witness that battle between the forces of Wakanda and these invaders, as they fight, each one pushing hard against the other. The war rocks Wakanda to its core, requiring the full attention of King T'Challa.
However, N'Jadaka has another, alternative objective. In order to pose a greater threat to T'Challa, he must find a new body. He must find his Marvel Universe equivalent: Erik Killmonger, Black Panther's greatest adversary.
Killmonger might be most well-known to audiences thanks to the film Black Panther, but that film doesn't go into one of Killmonger's most noteworthy traits: he comes back to life a lot. Every time Killmonger appears to be dead for good, he gets resurrected through some sort of scientific or mystical means.
While Emperor N'Jadaka might be dead, his symbiote can transfer his consciousness from one body to the next. Now, the aged N'Jadaka wants the younger, stronger body of his alternate universe self in order to better conquer this brand new world and extend his own life.
While the battle between his forces and the Marvel Universe Wakanda rages on, Emperor N'Jadaka transfers his symbiote over to the younger Killmonger, restoring life in the otherwise lifeless corpse of his counterpart to kill Black Panther and overtake this brand new world.
Can Symbiotes Do This?
While it might seem bizarre for a symbiote to bond with a corpse and overwrite the personality of its host, there is precedent for this kind of thing. The symbiote Sleeper hauled around his Kree host Tel-Kar across the galaxy, where the symbiote's consciousness overtook Tel-Kar's body after his death.
On the other hand, the symbiote blending perfectly with a host, as this symbiote did with its Killmonger, is less common. The Carnage symbiote bonded so perfectly to Cletus Kasady that they referred to themselves as "I" rather than "we." Furthermore, we see that different personalities can influence symbiotes, as seen when the Venom symbiote's personality alters depending on the personality of its host. For example, after bonding with Flash Thompson, the symbiote felt driven to do more heroic things, finding his immediate host after Flash, Lee Price, particularly grotesque.
However, Emperor N'Jadaka has the benefit of using Wakandian technology to further his control over the symbiote, allowing his personality to overlap that of the symbiote, which he sees as a weapon to be controlled.
This raises several questions about the nature of the bond between the Killmongers and this symbiote. With one Killmonger transferring his essence to another, this Killmonger could have two very different personalities. It's not clear if the symbiote is just using the dead corpse as a puppet or if Killmonger's body still has a secondary consciousness with the memories of its former self.
If the former, then Emperor N'Jadaka sees nothing wrong with using people like pawns -- even himself. However, if the latter is true, then that means that Killmonger's consciousness could awaken within the symbiote-controlled shell, setting up a conflict between the two Killmongers. While this alternate reality Killmonger wants to conquer worlds, his first Marvel Universe conquest could end up being his new body.