Time of Day
From WikiRaider
There are two different Times of Day in Lara Croft and the Temple of Osiris: Nighttime and Daytime. To select one of them, the player has to turn the inner of the two mechanisms in the Osiris Shrine Interior location of the Overworld. If the lever points north (to the top of the screen) it is daytime outside. Likewise if it points south (bottom to the screen) it is nighttime.
The outer mechanism selects the Seasons.
