The Gray Boys Mutants are failed experiments from the Gray Boys Science Lab...
Want a mutant?
Head over to https://opensea.io/collection/grayboys and get a Gray Boy.
Then, head over to https://opensea.io/collection/grayboys-science-lab and get some red and green serums to mutate your Gray Boys.
Now, head over to the science lab and perform you mutation experiment! https://lab.grayboysnft.com/