Arena Closer

The Arena Closers appear when a match of Domination or Mothership is finished or when a server closes in Free For All or Team Deathmatch.

No new players can join when the Arena Closers come and all players killed by an Arena Closer are redirected to another server. The Arena Closers have an insane amount of health, but the amount of health they have is unknown.

Design
Arena Closers used to have a small circle base but in the newest update, the arena closers have a larger size. The Arena Closer features a large circular yellow base with Destroyer's barrel, it is very similar to the Dominator without the hexagon base.

Technical
The Arena Closer shoots massive, yellow bullets which have a high velocity and can kill any tank with no more than 3 direct hits depending on the upgrades. They can see across the entire map. Also they can see cloaked Managers and Stalkers.

Strategy
The purpose of Arena Closers is to close the server; players killed by Arena Closers are then kicked from the server, then the server restarts when all players are killed. They are essentially invincible, so fighting them is not an option. Escaping is virtually impossible, as they are faster than the Fighter, Tri-Angle, and Booster class, even with fully upgraded movement speed and reload combined. However, a Sprayer can outrun them with fully upgraded movement speed and reload, but for a short amount of time before they spawn too close.
 * Strong Against: Every tank in the game
 * Weak Against: Nothing

Stats
The Arena Closer has the penetration and bullet size of a Hybrid, the Bullet Damage and Bullet Speed of an Assassin, the Speed of a TDM Guardian, the size of a Dominator, and an undefined insanely high (but finite) amount of health. It is hard to determine whether the Arena Closer has health regen or not, as the health is undefined and not visible like normal damaged players.

Trivia
For how they close an Arena, see here: Arena Closing.
 * On July 31st, 2016, Arena closers' spawn was delayed by a few seconds after message "Arena Closed: No players can join.".
 * This is the only tank that is yellow (aside from unclaimed Domination Turrets).
 * Aside from its yellow color, an Arena Closer's design is very similar to that of a very high level base tank which is slightly smaller than a Mothership so its level might be 140 or slightly lower.
 * Despite being very large, the in-game number implies that it has a score of 0. This was later removed.
 * It was originally much easier to escape the Arena Closers, as both their movement and Bullet Speed were slower than they are today. Some were able to survive their onslaught with maxed out Movement Speed and Bullet Penetration, such as Chini, a diep.io Youtuber. (https://www.youtube.com/watch?v=aoIfitMrAss)
 * They were buffed to their current strength and speed in the same update that added the Domination Gamemode.
 * They were buffed again to being a lot bigger, so they can deal body damage, it now shoots bigger bullet that is the size of a Destroyer's, making it harder to dodge them.
 * In the newest update, Arena Closers no longer has collision box, which mean they won't be pushed back by damage
 * Arena Closers spawn at Domination Turrets when a game of Domination ends.
 * Turrets in Domination never attack Arena Closers, but the turrets can still hit them by accident.
 * Alternatively, Arena Closers can accidentally shoot Turrets as well, but do not actively target them.
 * Their body and bullets can't harm or destroy polygons, but will shove them out of the way.
 * In the latest update, the Arena Closers will avidly attack the Dominator Turrets after destroying most of the players, which instead of being took over, will die.
 * Arena Closers will always go for the surviving Mothership first at the end of the Mothership game mode.
 * Guardians don't target them.
 * If you get 'killed' by an arena closer in Domination and Mothership, you don't actually get sent to a new server to play in. Instead, you are sent to the same renewed server.
 * When all players have left/been killed, the Arena Closers stop moving and shooting (as seen in the death camera), as their AI has no valid target to track/shoot. They also begin using the Auto-Spin function and slowly drifting, similar to the polygons (also seen in the death camera).
 * When Arena Closers kill Motherships they just bump into them.
 * Since the Arena Closers became giant, the alive Mothership are killed more quickly since there bullets are massively stronger and their body damage seems to be increased as well, they just bump straight into the Mothership
 * As this page says, they have limited health.