A glowing and moderately aggressive life form was found in the alien world as soon as night came.

4 years ago
0.14 - 0.15
4 years ago
Latest Version:
15.1.1 (4 years ago)
Factorio version:
0.14 - 0.15
1806 times

Short description:

This mod adds will-o'-the-wisps which spawn mainly in forests at night time:

  • Yellow will-o'-the-wisp
    • They live in forests and do not attack first.
    • They mainly spawn by the destruction of trees at night time.
  • Red will-o'-the-wisp
    • They live under stones.
    • Physical damage leads to fast replication process.
  • Purple will-o'-the-wisp
    • Will-o'-the-wisp in the state of spore.
    • They cause the corrosion of structures around and have a devastating effect on solar power plants.

UV-light is the only solution to reduce a lifetime of purple will-o'-the-wisps at night. Also affects on other types of the wisps.

Useful hints and tips:

  • Do not burn forest at night;
  • Each tree which was destroyed or mined by the player at night time has a chance to spawn the yellow wisp;
  • The elements of production (like belts, inserters, crafting machines..) are not susceptible to the corrosion damage in order not to irritate players beyond measure;
  • Small electrical poles are resistant to corrosion because they are manufactured from an alien wood;
  • If your turrets somewhere killed a wisp, try not to meet the wisps that night;
  • It is better to shoot the wisps in the direction of the wind;
  • Effects of the overlapped UV lights are summed (since v.14.22.9).
  • You can destroy the place in the woods from where the purple wisps are spontaneously flying at the moment to your base;
  • The wisps do not appear in the forest with a density lower than 200 trees per chunk (This value can be adjusted in the config).

//to be continued//

Modification history

14.22.2 - initial release for version 0.14.22
14.22.3 - Fixed: "The UV lamp reverts to a regular lamp when picked up.". Fix of the potential desync.
14.22.9 - The UV lights were reimplemented. The detector of wisps was added. Added support for mods with changed night duration. Fixed: issue with the unlock of recipes on an existing game. The source code was refactored to eliminate the potential desyncs. Some forgotten refinements.
14.22.11 - The missing corrosion protection issue with ShinyBob most likely fixed. Support for the modifications with the long night was updated: the wisps will be active for 3 minutes every 9 minutes without the continuous rise from trees. A small chance of appearing of Reds in forests added. The average TTL of the wisps was reduced. The input R signal was added into detectors. R = the custom range of detection. Some balance tweaks.
14.22.12 - Balance tweaks and the config file improvements.
15.1.1 - Update for 0.15.1