Iifa Tree (Final Fantasy IX)

The Iifa Tree, read as iifa Tree and sometimes mistaken as the Lifa tree, was planted long ago by Garland as a gigantic soul filter, filtering the souls of Gaia. It is located on the Outer Continent.

The dwarves of Conde Petie refer to the Iifa Tree as the Sanctuary, because after going through a ceremony, not unlike being married, the happy couple journeys to the Iifa Tree to inscribe their names.

Nature
According to the Final Fantasy IX Ultimania what is seen above the surface is not the true Iifa Tree, but just part of the tree's roots. The true part of the tree resides underground and reaches all the way to the planet's core, while its roots zigzag around the world just beneath the surface.

History
The Iifa Tree first originated from Terra and is over 5,000 years old. It was transplanted to Gaia by Garland after the Terrans' failed attempt at fusing the two planets into one. As a result of the failed fusion, Gaia's landscape was left in ruin, and in order to oversee the world's recovery, Garland moved Terra's magical tree Iifa to Gaia. Garland could use the Iifa Tree's roots to stabilize the environment, but it still took thousands of years for the planet to recover from the disaster.

Around 3,000 years before the game's start, Garland used the Iifa Tree to block Gaian souls from returning to their crystal in the planet core, halting the planet's soul cycle. Garland's plan was to only allow Terra's souls to cycle. Around 1,800 years before the game's start, Garland built the Soul Divider at the tree's base to replace the rejected Gaian souls with Terran ones so that the Terran civilization might one day be revived. The Mist that covers the Mist Continent is a by-product of the filtering process and is expelled from the tree to the Mist Continent through the tree roots.

Soul Divider's Destruction
Zidane and his friends are lead to the Iifa Tree by Eiko in order to find Kuja. Eiko dispels the barrier surrounding the tree created by Carbuncle, and the group proceeds to enter the Tree's trunk through a maze of roots. They find a platform which allows for descent into Iifa's depths, where the Mist breeds powerful monsters, and the interior of the tree glows a blinding green.

After riding a leaf-like protrusion even farther down the tree, Zidane, Garnet, Vivi, and Eiko marvel at the seemingly endless green pools below the harp-like structure of Iifa's base.

After Zidane examines the area with more scrutiny, the Iifa Tree begins to shake, and SoulCage, the Soul Divider, challenges the party. Despite SoulCage's assurances of his victory, he is defeated, and his demise triggers the disappearance of Mist from the Mist Continent. However, even with SoulCage gone, the tree still blocks the Gaian souls from returning to their crystal.

Shortly after, the area surrounding the Iifa Tree is the stage of a battle between Alexandria's army and Kuja. The battle ends with Kuja taking control of Bahamut and the Alexandrian forces being destroyed by the Dragon King.

Terra's Destruction and the Iifa Tree
After Terra's destruction, the Iifa Tree activates and expels enormous amounts of Mist all across the planet, and its roots protrude everywhere, cutting off several locations to the player such as the North and South Gates, Observatory Mountain, Ice Cavern, Pinnacle Rocks, Fossil Roo, Conde Petie, Conde Petie Mountain Path, the Desert Palace, Oeilvert, and Esto Gaza.

The portal to the game's penultimate dungeon, Memoria, can be found hovering above the Iifa Tree. A battle ensues with a swarm of Silver Dragons when the Invincible attempts to enter the portal, and the party fights a Nova Dragon.

After the party has defeated Trance Kuja inside Memoria and Necron in the Hill of Despair, Kuja teleports the party outside of the Iifa Tree with his magic. While the rest of the party depart, Zidane stays behind to look for Kuja. The Iifa Tree, however, is writhing and flailing furiously, and after Zidane finally manages to find Kuja, the Iifa Tree collapses upon itself, and presumably dies while possibly taking Kuja with it.

Locations
Iifa Tree lies on the northwestern side of the Outer Continent. Its roots spread out across most of the land surrounding it, with a few sparse forests nearby.

The entrance to the Iifa Tree is barred by a mysterious seal. Eiko explains that an Eidolon is sealed there and that only a summoner can clear the way. After some encouraging, she does so. Gargant Grass grows around this area, prompting Zidane to wonder if a gargant lives nearby.
 * Entrance

The dense, twisting roots of the tree provide a path for Zidane and the party to travel across in order to reach the trunk. The area is infested with monsters.
 * Roots

A short path inside the trunk reveals a Save Moogle and a descending platform that responds only to Zidane. This takes the party into the inner reaches of the tree.
 * Elevator

Mist and roots permeate even the inside of the tree. Blue treasure chests not seen in Gaia are scattered throughout.
 * Inner Roots

The lower depths of the Iifa Tree glow a bright green. A leaf-like elevator platform that again only responds to Zidane takes the party on a spiralling descent, with monsters attacking as they go.
 * Elevator 2

The green light grows brighter at the very bottom, which appears to have a structure similar to the shape of a harp. The light is so bright that the bottom cannot be seen; only swirling green pools are visible. SoulCage ambushes the party here and is defeated, ending the expulsion of Mist.
 * Bottom of the Tree

Treasure

 * Hi-Potion
 * Ether
 * Elixir
 * Phoenix Down
 * Remedy
 * Lamia's Flute
 * Healing Rod
 * Brigandine
 * Ruby (obtained automatically on entry)
 * Aquamarine (obtained automatically during the battle with Kuja)

On the roots

 * Stroper
 * Zombie X2
 * Zombie X3
 * Myconid X2

Inside the tree

 * Dracozombie
 * Zombie X3
 * Stroper
 * Soulcage (Boss)

Battle with Kuja

 * Mistodon
 * Mistodon X2

Surrounding Area

 * Nymph (Friendly)

Musical Themes
The theme of the Iifa Tree is called "Iifa Tree."

Etymology
Iifa is pronounced the same as, an word which means "beauty," but as a name, it is used more symbolically as an adaptation of the Latin , which comes from  חוה Ḥawwā and means "living." (The common English form of this name is .) Emphasizing the tree's superficial association with life, the circle-and-cross pattern on the front of the tree resembles the, an ian symbol for life.

The "world tree" is a motif in several religions and mythologies, represented as a colossal tree which supports the heavens, connecting the heavens, the world, and, through its roots, the underworld. This is similar to how Iifa Tree connects Terra and Gaia, and the "afterlife" in that it governs the soul cycle, and the roots of the Iifa Tree are very long, encapsulating the entire planet in their grasp.

It is also connected to the motif of the tree of life, a mystical concept alluding to the interconnection of all life on the planet.

Trivia

 * The Iifa Tree appears in Dissidia Final Fantasy and Dissidia 012 Final Fantasy as a trade accessory.
 * The theme song for the Iifa Tree in Final Fantasy IX is based on the moon's theme from Final Fantasy IV.
 * The Iifa Tree is also where the eidolon Leviathan is found.
 * It is only when Zidane stands on the lift devices that they activate; this is demonstrated when Eiko fails to move the lift alone. This may be because both the Iifa Tree and Zidane are from Terra and are therefore connected.
 * The Iifa Tree makes a cameo in Theatrhythm Final Fantasy as a location seen in the background of Final Fantasy IX FMS events.