Flank Guard

The Flank Guard is one of the five basic upgrade choices from the Basic Tank and can be selected at level 15. The Flank Guard can upgrade into the Quad Tank, Tri-Angle, Twin Flank or Auto 3.

Design
The Flank Guard features a circular base with a rectangular Barrel on the front that follows the cursor and an additional smaller rectangular Barrel on the back, with no debuffs according to size.

Technical
It adds a Barrel in the back allowing it to attack the enemies while fleeing. The Barrel in the back has the same strength as the front one. Also, it adds a recoil that is opposite to the front one, resulting in the recoils canceling each other. That means you will not move when you are still with Auto Fire on. Currently, both Barrels will fire at the same time, however this has not always been the case: very early on the Flank Guard's Barrels fired one at a time with even timing in between shots. This was changed as very skilled players or people simply using spinbots could rotate the tank in a way that caused all the Bullets to go in the same direction, making the tank unintendedly powerful.

Strategies

 * As this tank is similar to the Regular Tank, but with a back cannon, it is generally not a good idea to go against other tanks that are at the same level as you or higher level than you (though the Sniper class can be picked on). Instead, continue farming up levels, and upgrade to a tank of your choosing.
 * The back cannon can be used in some situations to return fire while fleeing, or just to damage the incoming projectiles to reduce the damage you take.
 * The Flank Guard's back cannon can reduce the recoil from moving and firing at the same time, resulting in a marginal speed increase while firing on the move.
 * A strategy for this tank is to approach an area with a lot of Polygons. Dive in head first, then turn the cannon 90 degrees clockwise / anticlockwise. Both the cannons will fire at the Polygons, giving you a lot of XP within a short duration.
 * The Flank Guard has the least amount of distinct Tier 4s that only it can upgrade to out of all of the Tier 2s, this number being 2, those two being Booster and Fighter. All other Tier 4s that it can upgrade to are upgradable from other Tier 2s, one Tier 4 being upgradable from Machine Gun, and the rest being upgradable from Twin.