Could not find an existing duplicate question, but this may be due to not know how to describe the word/feeling!
For example, given the following sentence:
Francis could not look away from the blood-drenched vampire. The blood-soaked clothes and shimmering fangs were X
And X is specifically drawing upon the fact that the appearance is horrifying, horrible, scary, etc.
Similar words that come to mind but are generic in their motivation: hypnotic, transfixing
First question on this Stack so apologies if poor formatting!
Best Answer
According to the Oxford online dictionary the verb to petrify means by its primary definition
However it has the secondary, originally metaphorical, definition of
The the present paticiple of to petrify is petrifying which would fit well into your sentence.