Antonyms for the phrase "taking edge off" would be phrases that describe making something worse, harder, or sharper. Examples of such phrases are "sharpening the edge," "intensifying the pressure," or "amplifying the tension." These antonyms imply the opposite of what "taking the edge off" intends to do, which is to lessen or reduce discomfort or stress. By using antonyms, writers or speakers can emphasize the severity of a situation or highlight the challenge that needs to be overcome. Using antonyms can create a greater sense of urgency or tension, and help readers or listeners better understand the nature of the issue at hand.