Sayida showed no sign of dismay as her strike failed to harm the creature- she simply filed the knowledge away for later, then began to consider alternatives... She could see that Syut had managed to hurt one of the zombies, though, as had the magical bolt. Perhaps she could help in another way. As Syut started to move, Sayida moved as well, stepping behind the creature he faced and using the leverage of her staff and a well-placed kick to interfere with the zombie's slow movement.
OOC: move (5 foot step), intending to help Syut set up a flanking spot; Aid Another to attempt to improve his attack as well (1d20+3 attack, DC 10, to give Syut a +2 to hit). If a 5 foot step cannot get to flank she will move in a way that leads to a flank in the future, moving 5 feet per round until she gets position. (Describing as best I can without a map)