The true nature of time is poorly understood by modern scientists. These scientists can only see things in close proximity to the Earth and the present, and cannot see how things change in the spatial and temporal distance. In the local geography of time, it is curved, just as Einstein theorized. If you travel far enough though, the curves get sharper and sharper, until they actually become angles. When that happens, you begin to approach the home of the Hounds.
Since only a handful of humans have traveled that far in time, very few have seen the Hounds in their home. It is just as well, because once a Hound sees a traveler, he will chase after him until the traveler is caught and killed.
This predaciousness is so innate to their form, and so overpowering, that it overwhelms the senses and causes humans to perceive them as a wolfish shape regardless of their true form.
The Hounds travel through angles in spacetime, so one way to avoid one that is hunting you is to stay away from all angles of less than 120 degrees. The Hound is implacable, though, and if any such angle is introduced when a Hound is near, it will use it as a doorway to attack its victim. Outwaiting a Tindalosian can take a long time - they are capable of waiting for millenia.
Being hunted by a Hound - canon style
Catching a glimpse of a Hound of Tindalos is a hazardous thing at best - for if it sees you, it will follow you back through time and space. It's hunger is eternal, and it will eventually find you and take you out.
Approximately 30 days after such a glimpse, the Hound will catch up to it's prey, and stream out of an angle - perhaps the corner of a room, perhaps from where a bookshelf meets the wall - any angle of under 120 degrees will do. Smoke will issue forth from the angle, and the Hound will manifest itself.
Those being hunted who know anything about the Hounds will do their best to eliminate angles from their life. Such a person's home will have plaster in every corner, turning all angles to curves. Doorways will be modified to get rid of their angles. Such preparations must be very thorough: Just setting something flat with a straight edge on a table will create an angle of 90 degrees through which the smoke can emanate.
Being hunted by a Hound - a different take
It takes some time for a Hound to catch your scent once you return to the present, but once he does you are in for a mind bendingly terrifying experience.
It begins with the recall of childhood memories. A few weeks after travelling back in time and encountering the Tindalosians, a victim suddenly remembers that during childhood there was always a presence there, watching from the sidelines.
Every day, more memories surface. The memories become of times more and more recent. Perhaps they suddenly recall that the girlfriend they had in high school who moved away never to be heard from again was actually the victim of an attack by a bizarre wolfish creature. The memory of her moving was just a manufactured one, obviously made by the brain to protect itself from the trauma of such a terrible thing.
How could they have forgotten that terrible day when their grandmother was eaten whole by the monster that has been following them since birth?
The victim's past is changing as the Hound comes forward, following the scent of the victim's soul. The victim is experiencing this as surfacing memories that contradict what they previously knew.
After a week or more of this, they begin having clear recollections of the Hound being nearby recently. They know where the Hound will manifest because they remember seeing it leaping from that corner over there just a moment ago … IT'S HERE!!!