Agreeing that the book The Golden Bull has worship of false gods in it, however since the original question was asking about the intensity of the books within CTC rather than about the worship of false gods, I didn't mention The Golden Bull. I'm glad you brought it up though, so we can explain our reasons for choosing it.
We chose The Golden Bull because it does give a full picture of Ur during the ancient time period and does show the worship of pagan gods in a negative way, demonstrating that the people are in bondage to the moon god and live in poverty and in fear of the god, while the moon god does nothing for their plight. Those who worship the moon god are also seen in a negative, domineering light and do not reflect any love but rather rule by fear. It was one of the few books that shows the pagan gods in this way, rather than glorifying the god(s) as an "interesting" myth or legend where the god is seen as a hero (like the Greek myths for example) and was also one of the few books for this time period that did not include human sacrifice or graphic content. We felt it was an important book for showing the pagan state of Ur as kiddos would be reading about God calling Abraham out of Ur in their history spine at the same time as The Golden Bull would be read aloud. It was interesting to me, personally, to get a feel for Ur at the time of Abraham and made Abraham's answer to God's call seem all the more amazing to me. Knowing its content, we scheduled it to be a read-aloud allowing for discussion with your kiddos about it.
When choosing books for this time period as read-alouds, we definitely knew there needed to be 3 different read-aloud options to meet the various comfort levels of families who will be teaching through this time period. So, we put together a History Interest Read-aloud set, a Girl Interest Set, and a Boy Interest Set, making sure to fully explain our reasoning for including a choice of 3 sets and including a content warning on the History Interest Set on our website and in our catalog. This leaves the decision to the parent and allows them to be in the driver's seat when choosing the books they feel are most appropriate for their kiddos.
For anyone wavering on what to choose for reading aloud, you may just wish to lean toward the Girl Set or Boy Set as it is definitely safer for a sensitive reader and steers clear of history-related topics from this time period that may make you uncomfortable.
As far as Preparing Hearts extensions go, The Bronze Bow is the most intense and for a sensitive reader, you may want to read along with your child or talk with her about it as she reads. Beorn the Proud has a couple of intense scenes and Journey to America has some separation issues that a sensitive reader may dwell upon. The one to watch the most is The Bronze Bow.
Hope that helps!
Blessings,
Carrie