The Sims 3/Lunar cycle

Lunar Cycle is a game feature introduced in The Sims 3: Supernatural. It controls the moon during night time continuously and adds in moon phases to the game. The cycle may cause some bizarre events around a neighborhood. The feature is supported in every neighborhood, including those from the Store and custom neighborhoods. It cannot be turned off or removed from the game.

Players can check which lunar phase it is in the current neighborhood by looking at the moon icon in front of a Sim's portrait at the bottom-middle of the game UI. They also can check how many days it is until the full moon by hovering the mouse cursor over the moon icon. .

Moon Phases
There are eight moon phases in the Lunar Cycle. When starting a new save game, the first moon phase may be the First Quarter, unless the player "Set to Single Lunar Phase" in the options.

Options
At the game options, there is an "Environment Options" tab which changes the options of the Lunar Cycle. There are two options which are "Set to Rotating Lunar Cycle" and "Set to Single Lunar Phase",  obviously the player must choose one. These options are applied universally and not per saved game.

The player can set the duration of each lunar cycle from 2 to 10 days, by the multiple of 2. This can affect the moon phases. The default game setting is 6 days.
 * Set to Rotating Lunar Cycle

The player can set the lunar phase which will be carried out throughout the whole game.
 * Set to Single Lunar Phase

Effects on Sims' Behaviour
Nothing bizarre will happen on most moon phases. On the full moon however, some bizarre events will happen around the neighborhood.


 * Sims who posses werewolf powers automatically transform
 * Some Sims turn into zombies
 * Pets become skittish
 * Significantly more Ghosts

Fairies are affected by the lunar cycle as well. They gain the "Energized by Moonlight" moodlet, which changes in value over the cycle, being at its most powerful during the full moon. On the new moon, however, they gain the "Starving for Moonlight" moodlet, which decreases their mood slightly. During full moon, witches spend 50% less magic power and gains 25% more successful spell rate.