A few years ago just before I canceled my Netflix account there was this movie called "The Silence". The premise of this movie was basically that some hidden cave or something had these ancient, thought to be extinct, pterosaurs inside, and when they were released they took over the whole planet and killed most everybody.

Back in the early 2000s there was a movie called "Reign of Fire", and The premise of this movie was basically the same, except instead of pterosaurs they were dragons, but the same kind of apocalypse happened.

Both of these movies made me think about whether it would be feasible or not for such a creature to destroy the earth, or whether we would be able to take them out quickly enough. Imagine a creature was genetically engineered to be very efficient and to survive long periods of starvation, thirst, etc., and it was also Engineered to drop eggs off and leave them to hatch on their own, allowing it to spread quickly without putting all of its eggs in one basket (literally), and also engineered to have a desire to kill living things and only consume small amounts of its prey.

It doesn't seem out of the realm of possibility for such a thing to be engineered and released on the world as a means of killing everyone. What do you think? Do you think this would be impossible because of some kind of energy economics, diversity of biomes, etc.?

I suppose it would be even more efficient to engineer some form of insect that could survive in multiple biomes, and which is engineered to use venom to kill everything it comes across.