How do you go second form uub in dbz devolution?

In Dragon Ball Z: Devolution, to transform into Uub's second form, you first need to achieve Uub's base form. Once you have that, you can activate the transformation by pressing the appropriate button or key combination when you have enough energy. Make sure to check the specific controls for your platform, as they may vary. After transforming, you'll gain access to enhanced abilities and attacks.