Survival Mode

Sandbox Mode is the game mode in which players begin their world. Prior to starting a new game, the player has the option to customize their world and may set things such as the frequency of Hound attacks or the occurrence of seasons. When a new world is started, the player is set in a randomly-generated world and is told by Maxwell to find some food before night comes.

In order to enter Adventure Mode, the player must find Maxwell's Door, which is located somewhere in the world, though usually quite far from where the player first spawned.

Sandbox (Custom)
There are a total of 30 customization options available when creating a new world. These customization options serve to allow the player to tweak a world to their liking. Note that setting many of the options that concern spawn rates to anything above the "default" value will cause those resources to spawn outside of their native biomes. Examples include Reeds and Beefalos. The options are shown below:

Additional information concerning specific consequences of the customization options:
 * A long season lasts ~50 days.
 * A short season lasts ~10 days.
 * A long day is 14 daylight hours, 1 dusk hour and 1 night hour of the clock.
 * A long dusk is 7 daylight hours, 6 dusk hours and 3 night hours of the clock.
 * A long night is 5 daylight hours, 2 dusk hours and 9 night hours of the clock.
 * Resources, animals, and foods set to lots will spawn in every biome, with the exception of plants in Rockyland.
 * Rain set to lots is infinite.
 * When Lightning is set to lots, lightning will strike every 12–30 seconds.
 * More information on the frequency of Hound attacks can be found here.



Trivia

 * Although they are valid monsters in-game, the customization interface does not allow the player to tweak the appearance of Krampus or Mosquitoes.
 * Setting objects to "None", will not prevent them spawning in set pieces, such as trees around Maxwell's Door.

Bugs

 * If your character spawns with monsters near you, they can attack you before Maxwell finishes his intro speech. (Verified with Tallbirds.) Clicking will allow you to skip Maxwell's speech and react accordingly.