Lunar Ruins

Lunar Ruins is a bonus dungeon in Final Fantasy IV Advance. It is located at the "man on the moon" face on the Moon. It is unlocked by defeating Zeromus.

Trials
It contains 50 random floors, including Trials for each character, which are unlocked for each character if they defeat Zeromus, testing the player in multiple ways, and battles against Lunar versions of the Summons. After defeating one of these Lunar Summons, the player gains a Grimoire for that summon, and is able to summon the Lunar Summon in battle once. After completing a trial, the player also gets either an ultimate weapon or accessory for the character whose trial is completed.

Yang's Trial
Yang's trial is one of strength; the party must defeat many monks working in teams of 8. After defeating all these monks, the party fights Lunar Titan. After its defeat, Yang gets the Discipline Armband, which turns his Power command into Deadly, which charges and then triples the damage.

Edward's Trial
Edward winds up in an illusion of Damcyan Castle's ruins. The party is attacked by a Specter. It cannot be killed through normal means, but Edward uses Sing and instead of the usual effect, he plays a Requiem, thus giving the tortured soul eternal rest. All the Specters (blue flames) throughout the ruins must be settled. The party eventually reaches a room where a fight with Lunar Shiva ensues. After her defeat, Edward gets the Harmonious Ring as a reward, which changes his Sing ability into Chant.

Rydia's Trial
Rydia enters a cave filled with mist. She turns back into a child, and most of her summon monsters disappear. The party must find them and defeat them to gain them back. Finally, after defeating all of them, the mist dissipates, and the party fights Lunar Mist Dragon. After defeating it, the player gets the Mist Ring, which improves Rydia's summoning power.

Cecil's Trial
Cecil is addressed by an unknown voice, who tests his abilities to do good deeds as a Paladin. After completing several trials by doing good things, Cecil meets Lunar Odin who gives him a sword based on the success of his trial. If he does everything right, he gets his ultimate weapon, the Lightbringer. The player then fights Lunar Odin.

Rosa's Trial
Rosa heads into a town. She must heal the hurt people in the town, 14 in all. After healing as many as possible before the time runs out, the party fights Lunar Asura. After her defeat, Rosa gets the White Ring which turns her Pray command into Miracle.

Edge's Trial
Edge winds up in a labyrinthine castle ruin. He must find his way through this, which can be quite tricky. The Palace Guards around here drop Keys if defeated, which are needed for doors. After these ordeals, the player fights Lunar Ifrit. Edge gets the Hanzo Gloves, which turns his Steal command into Plunder, increasing the chances of a successful steal, as well as an attack at the same time.

Kain's Trial
Kain enters the town of Baron where there have been several murders. Kain investigates, and after a while exposes the culprit, a Guard. However, he does not feel content, and during the night, he sees Cecil walk into the Devil's Road house. Kain follows him and is warped to a strange mirror room. In the mirror, he sees the dark reflection of himself, which is tempting him to kill Cecil. Kain can elect to do this, but then the trial will end. Kain refuses, and fights a Shadow version of himself, as well as Lunar Bahamut, one-on-one. After his defeat, he gets Abel's Lance, his ultimate weapon, which allows him to Double-Jump and sometimes casts Tornado when he attacks, even if the enemy is immune to it, as well as the Dragoon Gloves, which increases his power.

Cid's Trial
Cid appears on an island, near his Airship. A person on the Airship asks him to fly him to a destination before the timer reaches a certain limit. Then at that destination, another person arrives and wants to be flown to another destination in a lesser time limit. After a while, Lunar Ramuh is angered about Cid flying all over his skies and attacks. After his defeat, Cid gets the Fiery Hammer, his ultimate weapon, which casts Flare at random when he attacks.

Palom & Porom's Trial
Both Palom and Porom must be in the party. Palom and Porom, must work as a team in this Trial. The player fights Lunar Leviathan, and Palom and Porom get the accessories Twin Stars, which enables them to cast stronger spells, including Double-Meteor, with the Twin command.

The Final Trial
After the character's trials, a special version of Zeromus, Zeromus EG, awaits. EG most likely stands for Easy Game, and this is supported by the fact he is the Zeromus sprite from the Easy Type version of Final Fantasy IV.