| relentless(adjective, animal, mean, hard, tough) |
| satanic(adjective, evil, cold, indifferent, wicked) |
| violent(adjective, mean, sharp, nasty, harsh) |
| diabolical(adjective, animal, evil, violent, wild) |
| hellish(adjective, evil, nasty, harsh, violent) |
| uncharitable(adjective, person, mean, ill, hostile) |
| uncompassionate(adjective, animal, hard, tough, severe) |
| devilish(adjective, animal, evil, violent, terrible) |
| evil(adjective, nasty, harsh, awful, violent) |
| horrible(adjective, awful, foul, disgusting, immoral) |
| implacable(adjective, animal, mean, hard, tough) |
| insensate(adjective, bad, hard, tough, severe) |
| insensible(adjective, bad, hard, tough, severe) |
| malicious(adjective, animal, mean, evil, nasty) |
| rude(adjective, mean, sharp, rough, violent) |
| tyrannical(adjective, hard, tough, evil, nasty) |
| unrelenting(adjective, animal, mean, hard, tough) |
| barbarian(adjective, rough, rude, violent, cruel) |
| extraterrestrial |
| malign(adjective, animal, violent, wild, cruel) |