The pale sucker beast experiment.
It was a joke of an experiment that the Mutant Organization developed back then and unleashed on an entire Earth city. It was created under the hypothesis of whether humanity can fuse with the ancient remnants of a once mythic race, called Vampires.
But the experiment was a failure in the end as those who were infused with the gene only grew pale and experienced severe itching in the sun. Apart from those, they were no longer any good in the experiment.
So, it was abandoned. But the Mutant Organization's way of abandoning wasn't to take care of it. They simply released the virus on an entire city and once they saw it didn't produce the exact effect, they simply took their spaceship and left.
This automatically pushes the problem on the neck of the EIA, who had to create a remedy for an infection they had no clue about.
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