BETRAYAL
The fall of KRAKOA and destruction of the Martian breeding pits was directly preceded by the betraval of mutants by Mister Sinister. Retrospectively, it is obvious that Mister Sinister was playing a longer game of self-interest that superseded any normal association or allance.
And while the failings of the Generation Four mutants were clearly a design flaw baked into their design, it is now believed that most of the "random" circumstances that led to the creation of Sinister's program were, in fact, orchestrated by him.
"The nature of that man, Sinister, reaches far beyond any hope of redemption. There can be no salvation for the devil himself."
Sinister was publicly executed by the Man-Machine Supremacy after defecting.
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