Dura replies with a twisting motion of her hand, and Grimmgang once more feels the air closing around him. As she retreats along the squid's head, the zombies advance up the stairs, moving with more alacrity than their kind usually displays.
SpoilerWill save at DC15 from Grimmgang, or be paralyzed.
Dura moves out of sight (of everyone but Shard, anyway) to I21 (the squid's back counts as difficult terrain, should it come up.) The zombies advance to N12, O13, and O14.