| Clue | Source | Date |
|---|---|---|
| Extremely hard not to get worked up, sleep having been cut short | ||
| Least emotional | The Telegraph Cross Atlantic | 05 Jan 2025 |
| Most obdurate | ||
| Least sympathetic | Wall Street Journal | 17 Jun 2023 |
| Most hardhearted or rocky | Universal | 13 Jun 2017 |
| Most hardhearted or rocky | ||
| Most heartless site's not flexible | ||
| Most hard-hearted | USA Today | 14 Dec 2015 |
| Most unemotional | LA Times Daily | 20 Aug 2015 |
| Most hard-hearted | ||
| Most unemotional | ||
| Maximally unfriendly | ||
| Most unfeeling | ||
| Least fit for farming | ||
| Most unfeeling | ||
| Hardest. |