Dice rolling tends to do this. Good thing about it is that enemies have the same string of bad luck that we do. Had so many fights where they all missed for a whole round.
I had this happen, and it was so bad that the main mob rage quit the fight.
The Phase Spider Matriarch missed so many times that she rage quit the fight. She seriously teleported out of visual range, and when my party cleared the adds and the one spider we had left, combat ended, with her no where to be seen.
She phased to the furthest corner of the cave. Just head towards the exit, she will probably be at the second floor of the cave.
