| Answer | Crossword Clue |
|---|---|
| NUT | Tough .. to crack |
| HARD | Tough to crack |
| ENIGMATIC | Tough to crack |
| POSER | Tough nut to crack |
| ENIGMA | Tough nut to crack |
| PECAN | Tough nut to crack |
| ACORN | Tough nut to crack |
| POSERS | Tough nuts to crack |
| POSER | Tough nut to crack. |
| NUT | Tough thing to crack |
| NUT | It's tough to crack |
| ACORN | It's a tough nut to crack |
| NUT | It may be tough to crack |
| NUT | Item that can be tough to crack |
