merciless (adj.)
- atrocious
- barbarian
- barbaric
- barbarous
- bestial
- bloody
- bowelless
- brutal
- brutish
- callous
- cold
- crude
- cruel
- cutthroat
- feral
- ferine
- ferocious
- fierce
- hard
- harsh
- heartless
- illiberal
- implacable
- inclement
- inconsiderate
- indifferent
- inexorable
- inflexible
- inhuman
- inhumane
- insensitive
- malevolent
- malign
- malignant
- mortal
- murderous
- noncivilized
- pitiless
- relentless
- remorseless
- rough
- rude
- ruthless
- sanguinary
- savage
- severe
- thoughtless
- tough
- tyrannical
- unappeasable
- unbending
- uncalled-for
- uncharitable
- uncivilized
- uncompassionate
- unfeeling
- unflinching
- unforgiving
- ungentle
- ungracious
- unmerciful
- unmoved
- unpitying
- unrelenting
- unremorseful
- unsparing
- unsympathetic
- unsympathizing
- untamed
- unyielding
- vicious
- wanton
- wild
It is far from easy to determine whether she [Nature] has proved to him a kind parent or a merciless stepmother.
