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Geosgaeno is a boss enemy from Final Fantasy X whose first appearance is underwater at the ruins of Baaj Temple. However, this battle is left unresolved and Geosgaeno can be engaged after obtaining the airship as an optional boss battle.

Stats

HP (Ovk)	MP	STR	DEF	MAG	M DEF	AGL	EVA	ACC	LCK	AP (Ovk)	Gil
32767 (32767)	128	36	50	40	50	48	0	50	15	4200 (6300)	1000

Attacks: Swallow, Stone Punch, KO Punch (special attacks are used in the optional second encounter only)

Weakness: Fire, Thunder, Water, Ice, Holy

Immune: Silence, Slow, Sleep, Doom, Threaten, Provoke, Power Break, Armor Break, Darkness, Petrify, Zombie, Death, Sensor, Scan, Delay Attack, Magic Break, Mental Break, Demi, Eject

Resistance: Poison (95%)

Poison Rate: 10% of max HP

Zanmato Level: 4

Steal: Water Gem

Drop: Power Sphere

Strategy

First Encounter

As you may notice from the HP this battle will seem unwinnable. However it isn't. Firstly, although his first hit will worry you it only takes 1/2 your HP each hit, therefore, yet again its very difficult to die, also the battle only lasts 3 turns for each side, the only tactic here is to just do normal attacks against it until the battle ends.

Optional Encounter

Equip Tidus, Wakka, and Rikku with a weapon that has an element attached to it. When Geosgaeno swallows a character, their positive status becomes his. (If Rikku has Haste and is swallowed, Geosgaeno recieves Haste). Geosgaeno explodes at the end of the battle, so cast Protect or have Rikku Mix a Mighty Guard.