Sandbox

Sandbox allows playing 4 styles of maps: Campaigns, My Maps, Workshop Maps, or Random Maps

Sandbox gameplay mode is an excellent way to test out options and set-ups, built robust colonies and logistics set-ups, or play without victory conditions.

Option Descriptions

Map - Choose the starting/base map from these options: Campaigns, My Maps, Workshop Maps, or Random Maps
Active Mods - (not shown) - Select from Available Mods or from Workshop Mods
Colony Colour - Change the color of Colony Ship
AI Players - Available when a selected map has AI enemies; OFF - disable AI enemies; CASUAL - much less aggressive enemy; NORMAL - standard enemy capability; HARD - more aggressive enemy
Territory - ON - Must use Watchtowers to expand the territory; OFF - the entire map is visible and available; Watchtowers are not needed for expansion (Note: Maps with AI cannot disable Territory)
Fog of War - ON - available only if Territory is on; complete darkness at the end of the visibility; OFF - the entire map is visible.
Market - ON - Allows use of Space Ports for buying and selling; OFF - disables Space Ports
Unlimited Space Ports - ON - Allows unlimited Space Ports; OFF - buy and sell to increase Trader Reputation which will increase the number of available Space Ports
Technology Researched - NONE - No technology is researched; EVERYTHING - all research is complete allowing all buildings to be enabled/constructed
Free Construction - ON - Each building placed is instantaneously active; OFF - normal construction requirements and time
Free Storage Yard Resources - ON - Resources can be added immediately to Storage Yards (scroll to bottom of Resource tab in each Storage Yard); OFF - normal Storage Yards behavior
Upgraded Road & Path Placement - ON - Allows for any of the available road types (dirt, stone, brick); OFF - upgraded roads require Road Layers
Unlimited Monuments - ON - Allows unlimited Monuments; OFF - limited 1 monument of each size
Unrestricted Elevated Rail - ON - Allows unlimited elevated (unsupported) rail Tracks; OFF - limited to a length of 8 unsupported rail Tracks

Most Sandbox settings can be changed in-game (via info Mission Info button), however, Technology Researched=Everything can not be reverted.