The phrase "hitting unexpectedly" can be replaced by a few synonyms to add more color and variety to your writing. Some alternatives include "striking unanticipated," "slamming suddenly," "assaulting out of nowhere," "pouncing without warning," and "ambushing unexpectedly." Each of these phrases has its unique emphasis and tone, so choose which one best fits the context and tone of your text. Whether you're writing a novel, blog, or article, using different synonyms for the same phrase adds nuance to your writing, making it more expressive and engaging.