The phrase "dealt a blow" generally refers to a negative event, such as a setback, disappointment or injury. To express the opposite or positive experience, we can use antonyms like "blessing," "fortune," or "success." Alternatively, we can use words that convey the idea of overcoming adversity or bouncing back from a challenge. For instance, "triumph," "victory," and "conquer" are all suitable antonyms for "dealt a blow." Other possible antonyms include "achievement," "gain," "growth," "progress," and "prosperity." Whatever antonym we choose, its usage depends on the context and the severity of the event.