Northern Cave (Final Fantasy VII)

The Northern Crater (大空洞—Daikūdō, "Great Cavity") is the Final Dungeon of Final Fantasy VII. It is a massive crater that takes up much of the Northern Continent. Because the Crater is such an enormous wound to the Planet, huge amounts of Mako are brought here to heal it. This, in tandem with the Continent's titular proximity to the North Pole of the Planet, makes most of the Northern Continent a frozen desert. The cliffs that make up the Northern Crater's sides are the location, Gaea's Cliff, and on its top is the Whirlwind Maze. The inside is filled with a large cave system where the game's most powerful monsters reside. Sephiroth waits here as the Final Boss.

Final Fantasy VII
The Northern Crater was created by the original impact of an asteroid or meteorite containing Jenova thousands of years before the start of Final Fantasy VII. From here, Jenova began to destroy the Planet's lifeforms, until the Cetra sealed her there with the power of the Holy. The Planet placed its guardians, the WEAPON to lie here until another threat as great as Jenova appeared. Jenova was left dormant in the Crater until Gast Faremis working for Shinra unearthed her, thinking Jenova to be an Ancient.

Later when Sephiroth was defeated by Cloud Strife at the Nibelheim Mako Reactor, he traveled through the Lifestream to the Northern Crater to recuperate. Controlling Jenova and making her use his form, he leads the Sephiroth Clones there along with Cloud and his party to the Northern Crater for the Reunion. They bring with them the Black Materia, which is used to summon Meteor. The WEAPONs awaken, sensing the cataclysm above the Planet's skies, and rampage across the world. Sephiroth seals off entry to the Crater with a massive forcefield, and begins to remake his body to prepare for his ascension into a God. With their very existence threatened, Shinra uses the Sister Ray Cannon to destroy the Diamond WEAPON and blast through Sephiroth's shield. With the defense down, Cloud Strife and his party storm deep into the Northern Crater to defeat Sephiroth and release the trapped Holy, summoned by the fallen Aerith Gainsborough. There they find Sephiroth's new forms, Bizarro∙Sephiroth and Safer∙Sephiroth. Despite the power of these bodies, both are defeated. Though the battle is over, Cloud fights a metaphysical form of Sephiroth in his own mind and defeats that too. With Sephiroth completely defeated, Holy is released in a massive burst. The party escapes on the Highwind before they could be caught in the uproar of magical energy.

Advent Children
Though Sephiroth and Jenova are defeated, Jenova's head still remained inside the Northern Crater. The Turks manage to steal the head out of the Crater before the Remnants of Sephiroth can grab it to resurrect the would-be God. Hunting for any other remaining piece of Jenova, Elena and Tseng enter the crater. But they are ambushed at the beginning of the movie. What occurs is left off-camera, so that the audience does not know if they lived or were killed. The two Turks do manage to survive, as Vincent states to Cloud, the two Turks were brought half dead to the Forgotten Capital and reappear briefly later in the movie, after being rescued by Vincent.

Items Found
The Northern Crater has significantly more items than any other location in the game.
 * Save Crystal - see Save Crystal Glitch
 * Guard Source
 * Power Source
 * HP Absorb Materia
 * Elixir
 * Magic Source
 * Guard Source
 * Mind Source
 * Mind Source
 * Megalixir
 * Hero Drink
 * Power Source
 * Magic Source
 * Remedy
 * Vaccine
 * Shield Materia
 * Imperial Guard
 * Hero Drink
 * W-Magic Materia
 * Counter Materia
 * Luck Source
 * Turbo Ether
 * Mega All Materia
 * Speed Source
 * X-Potion
 * Vaccine
 * Magic Counter Materia
 * Turbo Ether
 * X-Potion
 * Remedy
 * Elixir
 * Mystile
 * Elixir
 * Tetra Elemental
 * Megalixir

Entrance

 * 1x Gargoyle
 * 1x Dark Dragon
 * 2x Parasite
 * 2x Gargoyle

First Descent

 * 1x Scissors
 * 1x Dark Dragon
 * 2x Parasite
 * 2x Gargoyle

Second Descent

 * 1x Scissors
 * 1x Dark Dragon
 * 2x Parasite
 * 3x Parasite
 * 2x Scissors

Dividing Point

 * 2x Scissors
 * 1x Dark Dragon
 * 2x Parasite
 * 1x Scissors
 * 3x Parasite
 * 1x Master Tonberry

Graveyard - Hatchery and Spine

 * 1x Pollensalta
 * 2x Death Dealer
 * 1x Pollensalta, 2x Parasite
 * 3x Parasite
 * 1x Malboro
 * 1x Dragon Zombie

Grass Area

 * 1x King Behemoth
 * 1x Allemagne
 * 1x Armored Golem
 * 1x Master Tonberry

Water Area (2nd Screen)

 * 1x Christopher, 1x Gighee
 * 1x Magic Pot
 * 2x Magic Pot
 * 1x Allemagne
 * 1x Master Tonberry
 * 3x Mover

Core (Upper)

 * Jenova∙SYNTHESIS (Boss)

Core (Lower)

 * Bizarro∙Sephiroth (Boss)
 * Safer∙Sephiroth (Boss)

Lifestream

 * Sephiroth (Boss)

Dissidia Final Fantasy
The Planet's Core, where Jenova SYNTHESIS is fought, appears as Final Fantasy VII ' s representative arena in Dissidia. It is here that Cloud battles and defeats Sephiroth once again at the climax of his part of the storyline. Shortly after that, Terra also comes here to look for her ally, the Onion Knight, and loses control of her Esper powers, and Cloud steps in to "battle" her, although afterwards he explains that he was merely providing an outlet for her strength, allowing her to unleash her powers on him so that she could regain control. The Warrior of Light also fights Sephiroth on this arena to rescue Firion, and Cecil faces off against Exdeath here to defend Golbez.

The arena consists of a large circular platform at the bottom of the arena, with floating rocks and platforms surrounding it. Tendrils of the Lifestream connect the platforms and can be slid on. In the alternate version of the stage, after time has passed during a match, the various platforms and bases in the stage will start floating upwards (reminiscent of what happens after the battle with Jenova∙SYNTHESIS in the original Final Fantasy VII) and more strands of Lifestream will appear on the stage, EX Cores will teleport if the platform they are on is destroyed, and the Brave Pool will immediately and continually rise.

Trivia

 * It is speculated by fans that this was the original place of death for Aerith. Evidence to this can be found in the debug room, which can only be reached via cheating devices, such as Gameshark. In a room accessed through these methods, there is a hidden area that is a third rendition of Sephiroth's cave called the "Great Cave", which is a separate image of its own. This area has Aerith's Theme playing in the background.
 * In Dissidia, there is a moment when playing in the alternate arena, that when the various bases and platforms appear, should you execute your EX Burst in timing, the background while executing your EX Burst will be brighter than expected.