Wow that's low. I'm not even going to bother rolling since my natural 1 beats your 20.
You can't detect me at all, but I take some more actions.
I have mindsight, so I know your location, your creature type (like "Humanoid" or "Outsider", but not "Elf" and such) and your intelligence score.
OO:
SpoilerGreater Mirror Image (1d4+4)[1](5), move up to C11 +15 feet.
End turn.