It has a longer recovery time than a regular attack.
Long-range.
Penetrates Protect even though it is a physical attack.
Overdrive
Hellfire:
"Ifrit encases its foes in a swirling ball of fiery vengeance and detonates it for massive damage to all enemies. All of Ifrit's attacks can exceed 9999 HP damage once you have activated Wakka's legendary weapon, World Champion." - Final Fantasy X Official Strategy Guide.
