Bacon!
"So, here's the plan." Lucy explained. "You will summon your black skeleton army and attack the outer walls of the city. I will then rush inside, saying I felt a magical disturbance from the dungeon and the only way to stop the attacking skeletons is to allow me inside to correct whatever is going on.
From there I will insist that I bring my party with me, as I need their assistance in fixing the dungeon. After we get inside, you unsummon your skeletons and we go about our merry way, the city and lord being none the wiser."
"That's a pretty good plan." Joshua said. "You just think that up?"
"Nope, been thinking about it since we left for the dungeon." Lucy explained. "I was thinking we needed a way in and so I thought of one."
"Well thanks." Joshua said. "It is probably better than my plan to kill everyone."
"It very much is." Lucy said.