| 100% | DUD | 3 | Firecracker that fails to crack |
| 75% | DUD | 3 | Firecracker that fails to explode |
| 57% | DUDS | 4 | Firecrackers that fail |
| 54% | DUD | 3 | Firecracker that doesn't crack |
| 54% | DUD | 3 | Bomb that fails to detonate |
| 54% | DUD | 3 | Bomb that fails to explode |
| 53% | DUD | 3 | Something that fails to function well |
| 53% | DUD | 3 | Faulty item that fails to work |
| 53% | HOW | 3 | Question musical that failed to start |
| 52% | HAMELIN | 7 | Town that failed to pay the piper |
| 52% | IFNOT | 5 | "Should that fail to be the case ..." |
| 50% | AIRSHOT | 7 | Golf swing that fails to contact with the ball |
| 48% | ALSORAN | 7 | Horse that fails to finish first, second, or third in a race |
| 47% | POTATO | 6 | Crop that failed, leading to famine in Ireland |
| 47% | ALSORAN | 7 | Horse that fails to finish first, second, or third in a race (Hyph.) |
| 45% | FOOLSERRAND | 11 | Task that's sure to fail |
| 45% | EASYA | 5 | Course that's hard to fail |
| 45% | EASYAS | 6 | Classes that are hard to fail |
| 44% | LEVEES | 6 | Banks that are too important to fail? |
| 44% | EGG | 3 | Something that's cracked to make frittata |
| 44% | HIHO | 4 | Cracker brand that sounds like a greeting to a prostitute |
| 43% | EASYA | 5 | Class that's hard to fail: 2 wds. |
| 43% | FUSE | 4 | Circuit part that’s set up to fail? |
| 43% | EGGS | 4 | Ingredients that are cracked to make khai jiao |
| 43% | CODES | 5 | Messages that need to be cracked |
| 43% | EASYA | 5 | Class that's practically impossible to fail: 2 wds. |
| 42% | DOA | 3 | Like an idea that’s doomed to fail, in slang |
| 41% | CODE | 4 | Secret cipher that a spy may crack to uncover confidential information |
| 41% | EGG | 3 | Food item that needs to be cracked |
| 41% | CODE | 4 | Secret message that needs to be cracked |