The Lighting symbols within Mystcraft affect visibility throughout the Age (regardless of illumination from sky or blocks), and some have other effects. Exactly one is needed for each Age description.
There are three types of Lighting symbols:
- Normal Lighting: Gives default visibility according to local light conditions
- Dark Lighting: The world will appear dim, and visibility will be poor regardless of lighting conditions. Furthermore, sunlight will not burn undead, and will not pacify spiders or Endermen. Mob spawning is unaffected, and is still controlled by the actual lighting level as usual.
- Bright Lighting: Both terrain and mobs will be clearly visible even without light, similarly to Night Vision. However, mob spawning is likewise unaffected. This symbol will introduce instability into the Age.