From Final Fantasy Wiki

Gaia is the ability of of Geomancer Job from Final Fantasy V. It is an offensive skillset whose effects vary depending on the terrain on which the current buttle is taking place. There may be several different Gaia effects that may take place in a single type of battlefield.

Ability	Terrain	Effect	Images
Branch Arrow	Forest	Non-elemental-damage to one enemy
Sandstorm	Desert	Wind and Earth damage to all enemies; may inflict Blind
Gust	Plains, Drakenvale, North Mountain, Fire-Powered Ship, Castle Exdeath, Tule Area, The Void, Castle Basements, Big Bridge	Wind damage to one enemy
Tsunami	Beaches, Oceans, Walse Tower, Ship Graveyard	Water damage to all enemies
Will o' Wisp	Swampland, Caves, Pyramid of Moore, Mountain Caves, Interdimensional Rift, Istory Falls, Ship Graveyard, Library of the Ancients	Fire damage to one enemy; may inflict Confusion
Earthquake	Plains, Fire-Powered Ship, Drakenvale, North Mountain	Earth damage to all non-flying enemies
Leaf Dance	Forests	Wind damage to all enemies
Quicksand	Deserts	Instant Death to all enemies
Stalactite	Caves, Istory Falls, Cleft of Dimension, Castle Exdeath	Heavy non-elemental damage to one enemy
Branch Spear	Forests	Heavy non-elemental damage to one enemy
Desert Storm	Deserts	Wind and Earth damage to all enemies
Wind Slash	The Void, Towers, Plains, Castle Exdeath, Castles, Big Bridge, Caves, Mountains.	Wind damage to all enemies
Poison Mist	Swampland, Pyramid of Moore	Poison damage to all enemies and inflicts Poison
Whirlpool	Beaches, Walse Tower, Ocean, Ship Graveyard, Guido's Cave, Istory Falls	Reduces one enemy's HP to a single digit
Big Tsunami	Beaches, Walse Tower, Ocean, Ship Graveyard	Heavy water damage to all enemies
Maelstrom	Deserts	Reduces all enemy's HP to a single digit
Sonic Boom	Plains, Towers, The Void, Castle Exdeath, Cleft of Dimension, Pyramid of Moore, Ship Graveyard, Library of the Ancients	Reduces one enemy's HP to 1/4 of total HP
Cave-In	Drakenvale, North Mountain, Pyramid of Moore, Caves, Istory Falls	Earth damage to all enemies
Tornado	Plains, Towers, The Void, Drakenvale, North Mountain, Fire-Powered Ship, Big Bridge, Cleft of Dimension	Reduces one enemy's HP to a single digit
Bottomless Bog	Swampland	Instant Death to all enemies