The word that can substitute the given group of words is malcontent.
- Malcontent means a person who is dissatisfied and complaining.
- Heresy means a belief or opinion that is at odds with established religious doctrine.
- Malleable means easily shaped or influenced.
- Miser means a person who is extremely stingy and unwilling to spend money.
Malcontent is the most appropriate word for the given group of words because it specifically refers to a person who is dissatisfied and complaining. It is derived from the Italian word malcontento, meaning "dissatisfied." | 
