

Combat Achievements (commonly abbreviated CA) are a one-off set of combat-based tasks and challenges. They are intended to test the player's prowess in combat related content, ranging from endurance challenges, killing monsters under a set time limit, and restriction based tasks in which players must kill a monster in a specific manner.
Requirements: You need have max skills and max gears to finish these tasks.
| Name | Description | Type | Tier |
| Terrible Parent | Kill the Nightmare solo without the Parasites healing the boss for more than 100 health. | Mechanical | Grandmaster |
| Explosion! | Kill two Husks at the same time. | Mechanical | Elite |
| Perfect Nightmare | Kill the Nightmare without any player taking damage from the following attacks: Nightmare rifts, an un-cured parasite explosion, Corpse flowers or the Nightmare's Surge. Also, no player can take damage off prayer or have their attacks slowed by the Nightmare spores. | Perfection | Master |
| Sleep Tight | Kill the Nightmare solo. | Restriction | Elite |
| A Long Trip | Kill the Nightmare without any player losing any prayer points. | Restriction | Grandmaster |
| Nightmare (Solo) Speed-Trialist | Defeat the Nightmare (Solo) in less than 23 minutes. | Speed | Elite |
| Nightmare (Solo) Speed-Runner | Defeat the Nightmare (Solo) in less than 16 minutes. | Speed | Grandmaster |
| Nightmare (Solo) Speed-Chaser | Defeat the Nightmare (Solo) in less than 19 minutes. | Speed | Master |
| Nightmare (5-Scale) Speed-Trialist | Defeat the Nightmare (5-scale) in less than 5 minutes. | Speed | Elite |
| Nightmare (5-Scale) Speed-Chaser | Defeat the Nightmare (5-scale) in less than 4 minutes. | Speed | Master |
| Nightmare (5-Scale) Speed-Runner | Defeat the Nightmare (5-scale) in less than 3:30 minutes. | Speed | Grandmaster |