A Demoness is the toughest boss in the game. She is a hidden boss that will give the player an achievement if defeated (along with the Demon).
Contrary to other bosses, it's not required to kill her in order to progress in the game or to get the loot to build a unique item (She does drop the Demon's Skin but this item would usually be looted earlier, from the Demon). However its 20 Sapphire loot is still very useful.
Location[ | ]
The Demoness is located in the Great Cave Go in and go at the very most right, dig if necessary.
Strategies[ | ]
Using a Particle Sniper Rifle is very useful, going too close is not recommended as well as using a Particle Shotgun, make sure you have a jetpack with you for she is very fast. Building turrets is not effective against the boss. Turrets will only prove effective against the additional enemies present such as the particle birds and hell hounds, but should one stay constantly on the move it is possible to defeat her and the additional enemies without any turrets at all.
| Name | Icon | Speed | HP | Armor | Range | Damage | Number of attacks | Cooldown | DPS | Knockback Monster | Knockback Target | Drops (probability) | Remarks |
| Demoness | 
| 8 | 13000 | 15 | 40 | 15 | 5 | 1.5s | 50 | 0 | 20 |
|
Reference: Monsters data table.