HOME > guide > Customizations > Custom Cartridges
Your robots will gain experience points from battle.
Once enough EXP has built up, a robot will be able to level up and activate a special custom cartridge.
Cartridges enable a variety of abilities unavailable to low level robots.
Select a robot with enough EXP to level up and click the LEVEL UP button.
Next, choose which cartridge you'd like to activate. Finally, click the LEVEL UP button again to activate the cartridge.
*Cartridges cannot be changed once they have been activated. Think carefully about what ability you want to enable when leveling up.
As an example, we'll level this robot up using the "Stun Regain" cartridge.
Our Cannon Baller now has the "Stun Regain" ability activated, meaning he'll regain a little bit of HP whenever he is stunned by an enemy attack.
There are many different abilities available via custom cartridges. Try out different robots to find out what kind of cartridges they can activate.