A really bleak ending can also have a lasting impact. When there's no hope and the evil wins completely, it makes the audience feel a sense of despair. Take 'The Texas Chainsaw Massacre' for example. The killers are still at large at the end, and the survivors are few and traumatized. This kind of ending makes the horror more real and memorable.
An unexpected ending can do it. If the ending subverts the audience's expectations, like in 'The Sixth Sense' where it's revealed that the main character has been dead all along, it stays with the audience long after they've finished the story.
By creating a really creepy atmosphere. If it makes you feel uneasy just thinking about it, it has an impact. For example, the way 'The Shining' made the Overlook Hotel seem so menacing.
Endings that involve a sacrifice can also be very impactful. When a character gives their life to stop the horror, it elicits strong emotions. It makes the audience feel the weight of the situation and remember the story. For example, in some zombie apocalypse stories, a character might sacrifice themselves to save others from the horde.
The ending can create a lasting impact by leaving things unresolved. For instance, in 'The Turn of the Screw', the ending is ambiguous. We don't really know if the ghosts were real or just in the governess's head. This makes the reader keep thinking about it long after finishing the story.
A shocking ending can create a lasting impact. For instance, if the ending reveals that the real horror was something completely unexpected, like the main character being the source of the terror all along. This makes the reader reevaluate everything they've read.
The climax can create a lasting impact if it defies expectations. Maybe the couple that seemed doomed to break up actually finds a way to be together in a completely unforeseen manner. This element of surprise makes the reader remember the story long after they've finished reading it. Also, if the emotions in the climax are so strong that they make the reader feel as if they are part of the story, it will have a long - lasting effect.
A powerful ending can create a lasting impact by surprising the reader. If the ending goes against what the reader has been led to expect throughout the story, it stays in their mind. For example, if a detective story ends with the detective being the actual criminal.
It makes the audience feel a mix of emotions. It can be sad because the marriage is over, but also a bit hopeful as the characters seem to be finding their own paths.
By using a sudden shock. For example, a quick and unexpected death of a main character at the end can jolt the reader. Like 'She was running away from the monster, and then, boom, she fell into a bottomless pit.'
It leaves a very emotional impact. The ending is so poignant that it can make the audience feel a deep sense of satisfaction. After seeing Alvin's long journey, the end where he meets his brother is like a fulfillment of a great quest.
The Suros Regime may have an impact on the audience in terms of making them think about power, order, or the implications of a certain system. A horror story impacts the audience by scaring them or making them feel uneasy.