Well, I've never seen Durandal act like THAT before. There's really not much to say about this, as it's just the prologue, after all.

As to possible problems, you hit the nail on the head in your summary: the OC sounds both omniscient and invincible, which could very well kill all sense of jeopardy for him. Of course, since we haven't even met him yet, it's possible that things are not as they seem.

One question though. You established that Shinn, Rey and Luna barely survived their first encounter with this OC, and that Durandal is willing to get Shinn killed if it stops the black suit. Are you planning to kill Shinn, Rey and Luna? I'm not saying you can't write that; it's your story and you should feel free to write whatever you want. I just want to know whether or not to stop reading.