What Did Immortal Mean When He Said They Found A Cure For Invincible S Sickness

How Did Mark Get Sick in Invincible Season 3?

As I mentioned above, it is unusual for Mark to get sick since he is part-Viltrumite and is immune to all the diseases found on Earth. However, what if Mark got sick with something that was specifically engineered to hurt Viltrumites? If we look at the comics, Invincible#67 introduced us to the Scourge Virus that was responsible for killing a huge majority of Viltumites leaving only a few survivors. It is one of the weaknesses of Viltrumites that can kill them.
In Invincible Comics, Mark was infected and got sick with an improved strain of the Scourge Virus that took away his powers. However, since Nolan comes from a superior royal bloodline, which makes Mark a royalty as well, he eventually fought off the virus and in time, his powers returned as well. It seems as if in the future when Immortal was made King by Invincible, he got infected with the Scourge Virus as well but since not much was revealed to us in the episode, we can’t say anything with certainty.
Now, if the Invincible Series introduces us to the Scourge Virus at some point, this theory can be reinforced so, stay tuned with us to know if that happens or not!