Upgrades are represented in the Class Tree, which will be shown as an image in a later time, as entities inside a series of concentric rings It can be displayed in-game by holding the Y key. In the direct center of the Class Tree is the starting tank; or Tier 1, or Level 1. The first ring contains Tier 2 (Level 15) tanks, the second ring contains Tier 3 (Level 30) tanks, and the outermost ring contains Tier 4 (Level 45) tanks. Areas shaded black on the tree indicate an unavailable Template:L in that tier.
There is a recurring pattern of colors in the upgrade selection menu and the Class Tree. The first tank will always have a red background. The second tank will be orange. The third tank will be yellow. The fourth tank will be green. The fifth will be light blue. The sixth will be blue. The seventh will be purple. The eighth will be pink. After this, the colors will loop.
|The tank you start out in Diep.io. The player has one Cannon that can destroy Squares in two hits, Triangles in five, and Pentagons in 22 with no additional Stats. The health, Bullet, and movement Statistics are average, and can be upgraded as you gain more points upon destroying Polygons and killing other players.|
Upon reaching Level 15, the player may choose to upgrade to one of these Tier 2 specializations:
Choosing the Twin class grants an extra frontal Cannon while damage and Penetration are slightly reduced.
Choosing the Sniper Class grants a broader field of view allowing the player to see further. Bullet Speed is also increased. However, Reload speed decreases significantly. Damage is not increased.
The Machine Gun sprays its Bullets in a frontal cone. It fires double the rate of a basic tank—the same rate of the Twin tank. It’s less accurate but it covers a wider area.
Choosing the Flank Guard class adds a Cannon on the rear. This allows the player to shoot in both directions to defend their back. Since both Cannons have identical Recoil, the Recoil effect is nullified.
Choosing the Blimp class replaces the front cannon with two back cannons that propel the tank forward.
Choosing the Hexer class increaces the Body Damage and movement speed of the tank.