While Aeris is a dab hand with any type of magic, support is where she truly shines. She excels as part of a team, her library of spells including the ability to augment attack and defense, heal party members, inspire fury, raise the defeated back to battle, and even render her allies temporarily invulnerable. As such, she generally prefers to fight with another person - it would be a waste of her talents not to.
Though she's not much of a physical attacker, Aeris also fights with a staff. It's obvious to anyone who sees her use it that she isn't formally trained with the weapon, but for her purposes, a hard whack to the head usually does the trick. She calls her staff the Princess Guard, and it becomes doubly effective when one of her allies have fallen.
Her physical defense isn't much better than her physical offense. Long range tends to better suit her strengths and cover her weaknesses.
Quake/Quara/Quaga - Casts offensive earth magic.
Water/Watera/Waterga - Casts offensive water magic.
Ultima - Casts powerful non-elemental magic.
Osmose - Absorbs MP from an enemy.
Dispel - Dispels an enemy's beneficial status effects.
Healing Wind - Heals herself or another person.
Seal Evil - Paralyzes and silences the opponent.
Breath of the Earth - Heals all status ailments.
Fury Brand - Triggers EX Mode for allies.
Planet Protector - Creates a shield that lowers physical and magical damage taken for all allies.
Pulse of Life - Revives fallen allies, or casts a heal over time spell on those still standing.
Great Gospel - Fully restores HP and MP of the party, including fallen members, and makes the party invincible for 3 turns.
Ex Mode - Promised Land
Aeris' hair falls out of her ribbon. Her magic attack is increased. She gains access to one new move:
Pray - Aeris is invulnerable for the duration of her prayer, but cannot perform any other action while praying (maximum 3 turns).
Ex Burst - Lifestream
Green tendrils of light rise from the ground and envelop the battlefield. This attack damages enemies and heals allies. It also dispels all buffs and debuffs, returning everyone's attack/defense to normal. The attack will also leave the enemy stunned for one turn.