Titan

Titan (タイタン, Taitan ?) is a summon from various games in the Final Fantasy series. Its attack, Earth Fury, sometimes called Anger of the Land or Gaia's Wrath, deals Earth-elemental damage to all opponents, but is useless against airborne foes.

Final Fantasy IV
Rydia can summon Titan. She summons Titan initially against Cecil Harvey and Kain Highwind in Mist when she finds out that they killed the Mist Dragon. Titan causes an earthquake and a landslide separating the Mist Valley from the Damcyan Desert.

Titan is obtained as a summon automatically after Rydia rejoins the party in the Dwarven Castle. In all non-DS releases, it has a casting time of 5 and costs 40 MP to summon, dealing non-elemental damage against all ground opponents. In the DS release, Titan costs 30 MP to summon and deals earth-elemental damage to enemies.

Final Fantasy IV -Interlude-
Titan returns as a Summon spell for the imposter Rydia and Rydia in the sequel of Final Fantasy IV. It's signature attack, Gaia's Wrath deals moderate non-elemental damage to all enemies at the cost of 40 MP.

Titan is wielded by the Tunneler, one of four Eidolon-holding bosses found within the Lower Section of the Tower of Babil B10. Once it's defeated, it leaves behind an orb of amber light. The imposter Rydia claims the light and regains the ability to summon Titan during battle. Titan along with the other reclaimed Eidolons are later summoned by the imposter Rydia on B6 of the tower to battle against the party.

Final Fantasy IV: The After Years
Titan appears as a boss twice in the game, the first time being unbeatable and the second time being obtainable as a summon. He is initially controlled by the Mysterious Girl, and will come to his senses after the final battle with him.