If you are thinking about words related to violence, there are some suffixes you could use:
* -ant: A person who is violent (e.g., violentant)
* -ence: The state or quality of being violent (e.g., violentence)
* -ly: In a violent manner (e.g., violently)
Let me know if you had a specific word in mind, and I might be able to help you find the correct suffix!