mercilessly (adverb)

1. In the horror movie, the serial killer mercilessly chased after his victims without any pity or remorse.

2. Despite her pleas for forgiveness, he had no mercy and ended their relationship mercilessly.

3. In the mythological story, the gods punished the mortals mercilessly for their disobedience, showing no pity.

4. The villain mercilessly attacked the superhero, showing no mercy as he tried to defeat him.