Rotten tomatoes usually matches my personal tastes pretty well. Their Critics Consensus summaries are pretty blunt and entertaining sometimes. Here's the one for Fantastic Four (2015). "Dull" is my favorite part.
"Dull and downbeat, this Fantastic Four proves a woefully misguided attempt to translate a classic comic series without the humor, joy, or colorful thrills that made it great."
"Dull and downbeat, this Fantastic Four proves a woefully misguided attempt to translate a classic comic series without the humor, joy, or colorful thrills that made it great."