SITE 13 is a Cosmic Horror film. When Dr. Nathan Marsh awakens from a catatonic state in a mental institution, he must relive his last expedition by watching tapes from the site visit, only to discover he's unleashed an unstoppable horror.
The dog is led into the center of a circle (portal) and his leash is tied to a stake in the ground. A moment later the portal zaps the dog and it disappears almost instantly in a small cloud of black energy(?). No blood or gore is shown, but right before this happens you can hear that the dog is scared.
A dog is tied to a stake in a circle which does swallow the dog. The dog is treated very well up to that point and I am unsure if that truly counts as abuse but it may trigger people anyways.
There are a number of scenes where someone appears to be having a seizure but it is intended to read more akin to a Possession kind of phenomenon rather than a true seizure.