The battle is lost will the tank’s HP reaches 0, so consistently upgrading the tank is very important key fact throughout the game.
With the progression of the game you can collect and change different tanks, upgrade them and upgrade their skills. All of these can be done via the tank button:

Types of Tanks
With the start of the game the player is given Alvis, a single star tank with two skills. The players can unlock a two star tank at once by linking a google account.
More tanks can be unlocked by completely collecting the base heroes of a series. Each Hero series has related tanks and if you collect all classes of a specific rank in a Hero series, the tank will be rewarded.
Tank | Star level | Unlocks by |
Alvis | One | None |
Sudri | Two | Linking to a Google account |
Heidrun | Two | Acquiring all Flame series units at 1 star at least once |
Gulltopp | Three | Acquiring all Snow seriesunits at 3 star at least once |
Fenrir | Three | Acquiring all Crown series units at 3 star at least once |
Sleipnir | Three | Acquiring all Poison series units at 3 star at least once |
Thiassi | Three | Acquiring all Beast series units at 3 star at least once |
Audhumla | Four | Acquiring all Silverwing series units at 4 star at least once |
Hodur | Four | Acquiring all Orc series units at 4 star at least once |
Fafnir | Four | Acquiring all Dragon series units at 4 star at least once |
Rusalka | Four | Acquiring all Rusalka series units at 4 star at least once |
Demon | Four | Acquiring all Demon series units at 4 star at least once |
Dwarven | Four | Acquiring all Dwarven series units at 4 star at least once |
Vethrfolnir | Five | Acquiring all Seraph series units at 5 star at least once |
Einherjar | Five | Acquiring all Fury series units at 5 star at least once |
Upgrades
Tank upgrades: A tank can by upgraded with gold spent. Each level up will increase overall stats of the tank. The amount of gold depends on the level of upgrade. The upgrade is capped at the current level your the players account.
Skills Upgrades: Each tank has two or three special skills unique to the=at tank. Whenever your tank’s level increases by 5, you can level up the tank skills. For detailed skills and stats of each tank click on their name individually in the list above.
