| terrible(adjective, revengeful) |
| unkind(adjective, mean, hard, severe, harsh) |
| demoniac(adjective, pitiless) |
| determined(adjective, harsh, cruel, fierce, persistent) |
| difficult(adjective, hostile, demanding, exacting) |
| dismal |
| fiendish(adjective, pitiless) |
| fierce(adjective, mean, hard, tough, severe) |
| hostile(adjective, person, feelings, response, demanding) |
| insensitive(adjective, hard, tough, harsh, cruel) |
| intractable(adjective, hard, severe, rough, harsh) |
| malevolent(adjective, mean, harsh, cruel, vicious) |
| rancorous(adjective, mean, harsh, cruel, vicious) |
| shameful |
| stony-hearted(adjective, revenge) |
| strict(adjective, hard, rough, harsh, cruel) |
| stringent(adjective, harsh, cruel, determined, fierce) |
| unmoved(adjective, pitiless, intolerant) |
| vicious(adjective, mean, hard, severe, rough) |
| antagonistic(adjective, reactive, reciprocal, vindictive, tit-for-tat) |