When it comes to expressing the feeling of being "frozen in shock and horror," there are several synonyms that could be used. Some of these synonyms include petrified, paralyzed, stunned, immobile, motionless, transfixed, dumbfounded, and stunned. Each of these synonyms slightly varies in context, but the gist of the feeling remains the same. Being paralyzed with shock and horror is a paralyzing feeling that can strike at any moment, leaving people with little to no control over their bodies or reactions. Using synonyms for this feeling can help lend descriptive and emotional power to writing and storytelling.