XP

C.o.c.kroaches are notorious for how good they are at surviving. A c.o.c.kroach can't be squashed and it wouldn't even die from a decapitation until weeks later when it starved to death.

They can also slip into any gaps of 3mm by compressing their bodies and at the same time maintain a speed of 60cm per second.

Their regenerative abilities are also top notch, easily able to regenerate their limbs, exteriors, and interiors.

They're also extremely good at adapting to everything. Things such as pathogens and bacterial/fungal infections don't really bother them. Their bodies also produce their own antibiotics.

Newer generations of roaches are also born immune to an ever increasing amount of pesticides. Their resistances increase around 5 fold with each generation.

(They also tend to spread bacteria such as E Coli)

The almost unkillable nature of c.o.c.kroaches may or may not have something to do with a failed experiment from way back, so sorry about that. Just treat it as test for humanity. We'd however recommend dealing with it within two decade or the consequences will be almost unimaginable with continents disappearing.