Well, they will have to hope that the ghouls' passive perception is not very high, because these two do not have stealth on their side, it seems. Meroon is shiny blue, and Caduceus is large and pink.

She nods, and begins to circle around where the undead have gathered. Holding her scroll-case two-handed like a war hammer, she charges out and clocks one on the head. The horde shuffles around to face her almost in unison.