When a cynical surgeon renounces his ancestral ties with a cabalistic tradition, he becomes the target of a dark force and must battle a phantasmagorical creature unleashed by the dark force to destroy him and everything he holds dear.

I like this one!

I see just a couple of problems,

1-the main character is passive ("he finds himself the target"). Focus about his actions, more than his reactions. What does the main character do?

2-"a supernatural, dark force that unleashes a phantasmagorical, savage creature to destroy him and everything he holds dear." this is a beautiful and rich prose but not appropriate for a logline. Too long and too vague an too complicated (a force that unleashes a creature... well A creature is enough!)

One more thing, "estranged" is one of the most used adjective to characterize the protagonist. And?I alwayes feel like?the writer failed to find a truly appropriate adjective. What I like is when?the adjective makes sense with the story, be linked to another element, it represent a flaw to be overcome.