Another way to create fearful suspense is to describe something terrible in great detail early on, and then make the reader wait for the scary thing to appear.
Here’s a snippet in which a grandfather describes terrible monsters. Notice how much more dialed-up the writing is compared to the previous understated snippet: this description has lots of vivid adjectives and words, all crowding together, trying to hype the monsters.
(Will the reality live up to the legend? You’d have to read to find out!)