William C. Young 
Parvon Zin Koban Hunter Book 3: Day of the Dinosaurs [EPUB ebook] 

The Anunnaki have returned, and they’re ready to reclaim control. The rebellious Adamu must be eliminated, making way for the new, genetically engineered and more compliant Adamex. But there’s a catch: how to accomplish this without demolishing the planet’s valuable infrastructure?Their solution? Unleash a relentless onslaught: millions of genetically modified Koban, pre-formed as dinosaurs, are sent to ravage the Earth. And just to raise the stakes, they plunge the world into darkness. Let the chaos begin.