The tank advancement feature becomes available once you upgrade the Command Center to level 24.

You can advance tanks or aircraft by clicking on the Logistics Center building in your base and selecting the type of advancement you desire.

There are four attributes you can advance for each unit type:
- Attack.
- Defense.
- Hp
- Speed.

The advancement process consumes Crystals, and there are two options: advance one time or advance level 1.

Advance 1 time consumes 1 Crystal and increases the advancement bar by a certain percentage. When the advancement bar is filled, one of the four attributes will be randomly increased.

With advanced level 1, the advancement level will be fully increased, and one of the attributes will be randomly increased.

Each unit type has a maximum advancement limit, and to increase this limit, you need to upgrade the building of the units you want to advance to the required level.

You can utilize the Lock feature to lock one of the attributes you wish to increase. To do this, click on the lock icon next to the attribute. When advancing, only the locked attribute's level will increase. Note that the Lock feature costs gold and may vary depending on the level difference between the four attributes, so please pay attention to the amount of gold required for each modification.

Master Feature:

When the advancement of all four unit attributes reaches a certain level, you can activate the Master Feature to gain additional attributes using various items and gold.