The Finding (Caldos Quest 1-12)

Synopsis
I've seen the same symbol in my father's old notes. My father explained to me that this symbol, when painted on an ancient slab, signified a secret passage. A few hours later, Alice found this symbol on a wall.

Completion
Wary of the risk, we pushed the slab with the stick of our shovel. Sharp stones started to fall right on the spot where we were supposed to stand. At the same time, the old heavy stone door squeaked open.