Crystals can be captured by either team by standing close to them.
Small monsters are swatted immediately.
Use them as often as possible for maximum damage.
As a result, buying items that offer both ability power and defense, like Zhonya's Hourglass and Banshee's Veil, can be a great choice to help her both survive and deal damage.
The cooldown is short and the mana cost is low.
Set them up in your team's backline before fights break out during sieges to help your team deal damage to the enemy frontline.