Fablehaven: Secrets of the Dragon Sanctuary

All is not as it seems to be.
Two hidden artifacts have been found. Three more remain unrecovered. More preserves face destruction as the Society of the Evening Star relentlessly pursues new talismans. Reading in Patton's Journal of Secrets, Kendra learns the location of the key to a vault housing one of the artifacts. In order to retrieve it, the Knights of the Dawn must enter a death trap--a dragon sanctuary called Wyrmroost. The mission cannot proceed without stealing a sacred object zealously guarded by the centaurs. Anybody seen Seth?
The race is on to acquire all five of the artifact keys to the great demon prison.