Eternal Summit

Abilities

 * Megaflare: Magic damage (21x) to all enemies.
 * Megaflare: Magic damage (14x) to all enemies.
 * 3 / 2 / 1: Inflict paralyze (100%) to all enemies.
 * Bolt: Lightning magic damage (3.2x) to all enemies.
 * Snowstorm: Ice magic damage (3.2x) to all enemies.
 * Atomic Ray: Fire magic damage (3.2x) to all enemies.
 * Nihility: Remove all status effects from all enemies.
 * Flare: Fire magic damage (4.5x) to one enemy, and decrease water resistance (30%) for 3 turns to one enemy.

Conditional attacks

 * Turn 1, and every 4 turns after (1, 5, 9, 13,...) : Megaflare, end turn.
 * Turn 2, and every 4 turns after (2, 6, 10, 14,...): Bolt.
 * Turn 3, and every 4 turns after (3, 7, 11, 15,...): Snowstorm.
 * Turn 4, and every 4 turns after (4, 8, 12, 16,...): Atomic Ray, Nihility.
 * 80% HP threshold (Once/battle): Bolt.
 * 60% HP threshold (Once/battle): Snowstorm.
 * 40% HP threshold (Once/battle): Atomic Ray.
 * 20% HP threshold (Once/battle): Megaflare (weak).
 * Threshold attack can only be casted on non-megaflare turn. If you trigger more than one threshold attack, they will be used on the same turn.

Regular attacks

 * Up to 7 actions per turn.
 * (Below 60% HP threshold) (Once/turn): Flare.
 * Normal Attack.
 * (Once/turn) Countdown.

Turn Count
Note: Threshold attacks and Flare are not listed. Threshold attack will trigger first, while Flare will trigger after elemental attack.

Tips

 * See testimonials and discussions.
 * Unless you are one-shotting him, this battle revolves around managing Megaflare damage.
 * Megaflare has long hit frames that will go through reraise.
 * A magic cover unit (Mystea) can cover all of the damage.
 * You can start with full LB/Esper by doing several battles before going into Bahamut.
 * Make sure you debuff Bahamut's MAG/SPR and boost your MAG. See here for a list of stat breaking skills and buffs.
 * Bahamut is incredibly easy to one-shot with the following setups:
 * Ring of the Lucii, a strong mage, and a Draco Spike. Break his SPR, buff MAG, and dualcast an Alterna to land inside your chain of choice (5* Shantotto works as a budget option if you lack any other chainers).
 * Zyrus (850+ MAG) and his limit burst are just as suitable if Ring of the Lucii is not an available option.
 * Any Summoner with EVO MAG +10% materia and Bahamut can act as a finisher to a high chain.