2 ferocious, inhuman, barbaric, barbarous, brutal, savage, bloodthirsty, vicious, sadistic, fiendish, diabolical, hellish, atrocious, Neronian or Neronic or Neroic:
His captors subjected him to the cruellest tortures.
Advanced English Dictionary
+adjective (crueller, cruellest) 1 (to sb/sth) having a desire to cause pain and suffering: a cruel dictator + I can't stand people who are cruel to animals. + Her eyes were cruel and hard. + Sometimes you have to be cruel to be kind (= make sb suffer because it will be good for them later). 2 causing pain or suffering: a cruel punishment / joke + Her father's death was a cruel blow. cruelly adverb: The dog had been cruelly treated. + I was cruelly deceived.
Collocation Dictionary adj
be, seem, sound | become
extremely, unspeakably, very
an extremely cruel regime
| a little, rather | deliberately | unnecessarily
I can't stand people who are cruel to animals.
Random quote: There surely is in human nature an inherent propensity to extract all the good out of all the evil.: Benjamin Haydon