Looking for a ‘horror’ movie title!

Ages upon ages ago, I saw the back end of a movie. It was rather old based on the quality of the film – so definitely nothing 2000-2020. I assume it was a horror film based on the different deaths that occurred during my short screening. All I remember from it was the protagonist (F) was initially surrounded by party guests who were all merry and boozed-up, from what I assume was a fancy dress party, however, were tasked with locating some crystal/diamond/gold eggs/treasures meant as party favors. I remember joining the film where one drunk man exclaimed that he had found one and a woman giddily laughed alongside him while the protagonist moved on (unamused and much more cautious, as though she knew something was up). I don’t recall all the events that took place, but I know that the number of party-guests seemed to dwindle, their bodies being found, or the protagonist stumbling upon their last breath. One pivotal scene (to me, anyways) right towards the end of the movie is where the protagonist finds another guest being beheaded by the swinging pendulum of a grandfather clock. She had tried desperately to save the guest, but to no avail. The protagonist then had to fight off some other crazy chick (maybe they were sisters fighting over the property?) who was later killed. The movie ended with music playing and the protagonist escaping from the mansion/house/castle and walking along a cobblestone path.

I would have seen these scenes when I was maybe 9 or 10 years old, and they’ve haunted me since – and thus I’m desperate to try to work out what this movie was called so I can rewatch it and make sense of the whole thing!

If anyone had any ideas please let me know!