Stukov didn't die. He developed a cloning technology in secret, and cloned himself. Later, becomng suspicious of Samir Duran, he went into hiding and released his clone into public, to replace him. Thus it was Stukov's clone that died, not Stukov himself. Two yeas later, Raynor discovered the cloning machine. He cloned himself. However, unbeknownst to him, The machine was damaged, and when Raynor cloned himself, a huge amount of gamma radiation was injected into the clone. Having the effect of thousands of gamma rays it accelerated the clone to millions of years later in evolution, makig raynor's clone the first ever Gamma terran.