From Final Fantasy XIV A Realm Reborn Wiki
Apex Arrow is an action unlocked at level 80. It's available for Bard.“
Delivers an attack with a potency of 120 to all enemies in a straight line before you.
- Soul Voice Gauge Cost: 20
- Potency increases up to 600 as Soul Voice Gauge exceeds minimum cost.
- Consumes Soul Voice Gauge upon execution.
— In-game description