Darkness
Darkness is a game mechanic that darkens the player's screen. Not having a light source in the darkest areas will cause rapid damage from biting insects, and the player will be unable to attack anything. The damage is lethal.
Light sources can dispel darkness to varying degrees, though even the dimmest will prevent damage from biting insects. Some dark areas have environmental hazards or hostile monsters that can extinguish weaker light sources, with higher tier light sources being resistant to these hazards while also being brighter.
Darkness levels
There are three different levels of darkness which may be encountered:
| Level | Effect |
|---|---|
| 1 | Slightly dims the player's screen. |
| 2 | Darkens the player's screen even more, potentially making it difficult to see the environment, but still has no penalties. |
| 3 | Almost completely obscures the player's screen. Without a light source, it is impossible to attack anything. After 9 seconds the player is warned, "You hear tiny insects skittering over the ground...". After another 9 seconds, there will be another message, Tiny biting insects swarm all over you! and one point of damage will be dealt after a set amount of ticks based on the location. This damage cannot be reduced by any means, but will stop upon igniting a light source or leaving the dark area. Logging out and back in will reset the damage timer. |
Dark areas
The following is a list of dark areas and whether each has biting insects or explosive gas, and also notes the insects' attack delay in ticks:
| Location | Darkness | Insects | Gas | Ticks between insect damage |
|---|---|---|---|---|
| Abandoned Mine bottom floor[1] | 1 | No | No | N/A |
| Chasm of Tears | 2 | No | No | N/A |
| Crombwick Manor upper level | 1 | No | No | N/A |
| Dorgesh-Kaan mine | 3 | Yes | No | |
| Dorgesh-Kaan South Dungeon | 3 | Yes | No | |
| Falador Mole Lair | 3 | Yes | No | |
| Genie's crevice | 3 | Yes | No | 1 |
| Kruk's Dungeon | 3 | Yes | No | |
| Lumbridge Swamp Caves | 3 | Yes | Yes | 3 |
| Mos Le'Harmless Cave | 3 | Yes | No | |
| Shayzien Crypts | 3 | Yes | No | |
| Skavid Caves | 3 | Yes[a] | No | N/A |
| Slayer Tower basement | 1 | No | No | N/A |
| Sophanem Dungeon | 3 | Yes | No | 1 |
| Temple of Ikov lower level[2] | 1 | No | No | N/A |
| Zamorak's Fortress[3] | 1 | No | No | N/A |
Dispelling darkness
The darkness level in an area is reduced by the cumulative strength of all carried and equipped light sources. Thus, carrying a candle in level 3 darkness will reduce the darkness to level 2, and another candle would reduce it to level 1. A built Fire of Eternal Light can also permanently dispel the darkness in an area, making a light source unnecessary.