- Unlock the Warrior
- Collect Zeo Shards of the Warrior until you have enough Shards (their experience bar fills and turns green).
- Go to Team Select (via the side navigation bar)
- Pull up the Roster menu and select the Warrior.
- Tap the Upgrade button below the Warrior
Increasing your Warrior's level will make their attacks do more damage and increase their health.
Note: Make sure you have enough Power Coins to level up the Warrior. If you don't have enough Power Coins, you can use Power Crystals.