Asmodeus at the end ("In a year and a day, you will be dead!").
Also, Asmodeus's attack on Susan comes across as quite silly forty years on, especially the close-up of the over-the-top kissing face he attempted on her.
The laughing old man, while initially unsettling at first, his No Indoor Voice while everyone tries to be more down-to-earth comes across as a bit silly afterwards.
Before they enter the cave, the group hears the laughter of the old man followed by the flapping wings of something, hinting at the terror that their doomed venture will ensue.
The Jump Scare of the skeleton followed up by the laughing old man, Vicki is exploring the cave when this man appears out of nowhere, freaking her out. He then offers the book and disappears for a short while. It's heavily implied that the events caused by the book have caused this old man to undergo an understandable descent into insanity to cope with the insanity he's witnessed.
Dr. Waterman, visibly out of his mind, attempts to take the book away from Dave and Jim, only to kill himself by accidentally hitting his head against a rock in the ensuing chase. His body suddenly disappears when Dave and Jim go back to check back on him.
The Attempted Rape that Asmodeus attempted on Susan, starting with the park ranger's visage gradually becoming demonic until he forces himself upon her, with uncomfortably close-up shots of initially his horse causing the scene to occur and then Asmodeus himself as he forces himself onto her. Thankfully, the cross she was carrying repelled him before it escalated even further.
Asmodeus in general, initially appears as a reasonable park ranger, but he's gradually hinted to be something unnatural as he has a habit of randomly appearing out of nowhere on his horse without hints of the latter moving, his face gradually becomes inhuman, and finally, he's revealed to be a StopMotion red-skinned, skull-faced demon with bat-like wings for hands, a trident tail, and taloned feet. Such feet are what he uses to kill Vicki by clawing her in one painful strike and proceeds to lift Susan up to then drop her to her death, nearly killing her.
The revelation that the book is a Persian book of demonology meant to summon demons. It's accompanied of imagery such as demonic statues and a group of robed cultists leaping into the red abyss as Dave narrates. He comments that the cultists felt that the desire of evil and destruction was a joy in of itself.
It is followed by Dr. Waterman's attempt to create a demon in a vain attempt to make it a breakthrough in scientific research, said demon, a StopMotion warped ammonite demon with uncannily human-like eyes destroys the cabin seen wrecked earlier in the film.
The closeup of Asmodeus-Jim with the makeup makes his eyesockets appear pure black, making him unnerving to look at. And his fight with Dave continues, his ears subtly more pointed and reddish- making his true demonic nature more apparent.
This leads to the beginning of the film where Dave is run over by a car without a driver, implied to be powered by the same robed creature from before. And when he's sent to an asylum after being reduced to madness due to no one believing him, he loses his cross and a certain possessed Susan arrives to finish the job...
The original 1967 cut manages to be even more frightening than the more popular 1970 cut, with several of the cut content causing the film to be more disturbing.
The towering pitch black reaper figure appears at the beginning rather than the end, having a much more raspy voice compared to the deeper voice of the 1970 cut. Making much clearer that Dave is being cursed to die in a year and a day by the forces of Hell himself. Dave immediately runs away as an understandable reaction.
While the 1970 cut has Dave being run over by a driver-less car implied to be empowered by the dark forces, the 1967 cut initially seems to have a driver that ran over Dave by mistake, which leads to the reveal in the next shot that it never had a driver, making the seemingly innocuous accident a shocking revelation that the curse was legitimate.
In the 1967 cut, Dr. Waterman meets his demise being chased by the demon ape, which is initially presented as a point of view shot from the monster, as the scientist desperately tried to escape only to be nearly killed by the demon in a state of terror.
In the 1967 cut, the the ammonite monster that Waterman summoned destroys Dr. Waterman’s cabin just before the group arrives. When the group gets there, they only see the wreckage afterwards. The lack of clarity as to what the monster was, hints that something unnatural is going on.
In the 1967 cut, when Vicki finds the foot print of the Asmodeus creature, it’s given more ominous emphasis that something inhuman is around.
In the 1967 cut, Waterman’s narration has him speaking in an ominous tone as imagery such as a robed figure in front of a blood-orange clock.
One of his recollections has him accidentally calling forth the damned in black robes commanded by a StopMotion skeleton demon in a dark cape with a pitchfork commanding the dead to fall into Hell.
In the 1967 cut, since Asmodeus was an addition to the later 1970 version, it’s not made clear what killed and replaced Jim, only that it’s not human. Additionally, the gradual transformation from Jim to the winged demon is mor pronounced with his final state prior to becoming the winged creature having reddish skin, tusks, and black devil horns. The StopMotion creature terrifies Dave just before the demon knocks him out with his wing.
Special Effects Failure: While the effects are impressive for the small budget and the fact that Dennis Muren (the special effects head/director of the original short) was 17 at the time for "zero money and very little resources of any kind, you sorta get by with what you can when you have a passion for doing something." The passion was there, but the budget was not.
