Sandbox

 is a game mode added on September 3, 2016. It is similar in style to Free For All, except that the map starts out significantly smaller. Unlike in other Game Modes, the Sandbox includes cheats — players can change their Level and/or Class with the simple press of a button. This makes Sandbox useful for testing Builds and for finding/killing Bosses.

Additional players may join a Sandbox arena, through the use of a party link. Players who use cheats have their name displayed in yellow, everyone else's remains white.

Size
The entire map starts smaller than a large Pentagon Nest (around 50x50 tiles), but Crashers and Alpha Pentagons very rarely spawn at the center. As additional players join, the map size will increase by 20x20 tiles per player. Increasing the size of the Pentagon Nest with it. Along with the chance of Polygons (Alpha Pentagons and Crashers) spawning in it.

Polygons
Much like with the size. The Number of polygons available in the arena will increase by 12,5 polygons for every additional player. Number which will then be rounded down to the nearest natural number. Polygons will respawn randomly 2 frames after one of them is destroyed.

Special Controls
(These keys are for the common QWERTY keyboard and normal settings. On other keyboards, the keys may be different.)
 * = Suicide (There will be a  message stating that you were killed by [your name])
 * = Switch classes
 * Cycles through Classes beginning with the most recently added tanks.
 * Includes (smaller versions of) all three types of Dominators, the Motherships, and the Arena Closers (all are the level of your current tank, but the smaller the level, the faster the speed)
 * = Level Up (hold down to gain Levels quicker)
 * Maximum level is 45, even for special classes (Dominator, Mothership, etc)
 * = Activates God mode, grants invulnerability, similar to an Arena Closer.
 * Note: may not work on some keyboards.
 * If you are not using an English (US) QWERTY keyboard, you can find the key to activate the God mode by opening an On-screen keyboard and changing the Windows keyboard language to see the position of the key.
 * God mode can only be used when only one player is on the server. This function will be automatically deactivated if a second player joins the Sandbox and when all the other players leave it will become available again.

Trivia

 * Dominators, Arena Closers and Motherships can be played in Sandbox, but because the maximum Level is 45, they will appear much smaller.
 * This is the only game mode in which Arena Closers and Motherships are playable.
 * Like in every other mode– random Bosses will spawn 10 minutes after the room is created and 23 minutes after the previous Boss despawns. Bosses will not give exp if in God Mode and the server will close after 10 minutes of inactivity.
 * Polygons won’t respawn at a certain distance from players, so if the map size is small enough and the player stands at the center of it, Crashers won’t spawn at all.
 * As a Necromancer, the number of Drones you can get will be directly dependent on the number of polygons available and thus– the number of players in room. (Due to Necromancer drones being counted as Shapes).
 * When playing with others, be wary of trolls, as they generally switch into Arena Closers.
 * As of September 4th, the arena size has decreased.
 * The Sandbox Cheats might be the Developer Cheats (probably with restrictions).
 * It was once possible to get achievements in this mode, that is no longer the case.

Bugs
{{BugList|

Possible Bugs
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 * Capturing all Squares in the Sandbox arena alone as a Necromancer will prevent any more Polygons from spawning until any of the squares are destroyed. A possible reason for this is that the captured squares are still counted as Polygons, and only twelve Polygons can spawn in the Sandbox arena when there is only one player.