This is how I'd add to the tutorial.
Intro: Spend mana by left clicking inside the green zone. Use 1-5 to select your ball.
Tip 1: Focus on mana regen at the start. Mana speed is good too
Tip 2: Mana damage is great for stoppiong
Tip 3: Switch up your ball types! You never know when you could trigger a huge combo!
I'll be watching this very closely...