When describing a violent situation or action, there are many different ways to convey the intensity and severity of the act. Some potential synonyms for "extremely violent" could include "brutal," "savage," "ferocious," "vicious," "ruthless," "merciless," "cruel," "barbaric," "bloodthirsty," and "heinous." Each of these words implies a certain level of cruelty or brutality, emphasizing the gravity of the situation. Depending on the context and tone of the language being used, some of these synonyms may be more appropriate than others. Ultimately, the goal is to choose a word that accurately conveys the severity of the violence while also fitting within the larger context of the narrative or discussion.