Sierra1

Question: Eric spent the last 10 years in prison, completely cut off from the outside world. How does he know everything about the Sentinel project and Trask? How does he know that Azazel, Banshee, Emma, Angel and many other mutants were tortured and killed?

Answer: It's possible Azazel, Banshee, Emma and Angel were captured before Magneto, so he knew of their fates before he was imprisoned. He may have been captured trying to rescue them, or tortured alongside them. And Wolverine could have told them about Trask and the Sentinel program.

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