brutal
brutish
SMART Vocabulary: related words and phrases
Unkind, cruel & unfeeling
acerbic
acerbically
acerbity
acidly
anti-cruelty
cruel
cruelly
cruelty
cruelty to someone/something
cutthroat
meanness
mental cruelty
merciless
mercilessly
mordant
trenchant
trenchantly
uncharitable
uncharitably
unchristian
bestial | American Dictionary
bestial
adjective
us/ˈbes·tʃəl, ˈbis-/
fierce and cruel, and without any human feelings:
a bestial dictator