Sandbox is a map that lets you test out stuff, or just have fun. In Sandbox you can use commands in the chat to anything, heres a list of all commands:
/spawnboss (boss class) (boss id)
/spawncelest (celestial name)
/spawnfinal (final boss name)
/shape (shape id)
/map (map id)
/mapsize (target map size)
/kill (things id)
/spawndom (dominator id)
/IDlist
/transform (thing id)
/kick (player id)
/team (me or thing id) (team id)
/spawnrift
/public (true of false)
/upgrade (name/id of upgrade)
what the commands do:
/spawnboss spawns a boss
/spawncelest spawns a celesital
/spawnfinal spawns a final boss
/shape spawns a shape
/map lets you change the map
/mapsize lets you resize the map
/kill lets you kill the thing you put the id of
/spawndom lets you spawn a dominator
/IDlist give a list of all the ids of the things in the room (which look something like this: iaOp-192) and under that gives a list of all shape/boss/dominator/ect ids in a list so you can spawn them which would look something like this:
(image of gunner dominator) dom1
(image of destroyer dominator) dom2
(image of hir) celest1
(image of ragnot) celest2
(image of krono) final1
(image hokon) final2
(image of elite skimlet) elite1
(image of pentax spawner) boss1
/transform lets you transform into something
/kick kicks a player from your sandbox match and doesnt let them rejoin for 20 minutes
/team lets you join or force something else to join a team
/spawnrift spawns a closed rift on top of you
/public lets you make your sandbox game public or not in the Sanboxes tab of the title screen
/upgrade lets you upgrade your tank, can be used for normal or Elite upgrades