Final Fantasy II/Mission to the Pandaemonium

A tough explanation
Firion and company, along with Leon, will return to Fynn. Upon seeing Leon, Hilda will demand to know what has happened. Firion will explain that the Emperor has returned from hell. Maria explains how Ricard sacrificed himself so that they could escape. Then she recounts all the others who have passed trying to aid them. Leon will then agree to join your team at Maria's request.

Return to the audience chamber and speak with Princess Hilda. She will mention the term Jade Passage which you can choose to learn. If you ask Hilda, Gordon, and Leila, you can piece together that the Jade Passage is essentially found in a small lake to the east of Mysidia. When you exit from Fynn Castle, you will find Cid's airship waiting for you outside.

Leon the black knight
Default weapons: axe and sword.

Despite his proficiency, leave the axes to Guy and the swords to Firion, and give him the best staves and spears, that would be otherwise unused.

Detailed analysis of Leon's weapon skills:


 * Axes L9: it's better to leave the axes to Guy, who can make better use of the white-spellcasting Rune axe;
 * Swords L8: it's better to leave the swords to Firion, who can make good use of the black-spellcasting Masamune sword;
 * Spears L7: after Leon joins you, soon a white-spellcasting Holy spear will be found, although Leon is more proficient with Black magic;
 * Staves L6: you should already own two black-spellcasting Mage's and Wizard's staves plus a Healing staff, so this is the choice;
 * Daggers L5: none has special effects, so ignore them;
 * Slings L4: it's better to leave the bows to Maria;
 * Shields L3: every character should use a shield to improve his/her evasion;
 * Karate L2: this is Leon's lowest skill, ignore it.

Equip Leon with a few black and a few white spells, just to improve his spellcasting abilities related to the special weapons he can use.

The Jade Passage
Hop in the airship, and make your way to the Mysidia region. Sure enough, if you travel east from the town, and follow the land as it juts out into the ocean, you will eventually notice a small lake near the end of the land mass. Land your ship and step towards the lake to enter the Jade Passage. Once inside, you will be facing, quite naturally, the toughest enemies you have faced so far.


 * Floor 1: There are two chests to obtain on this floor, one far to the right of the entrance containing the Diamond Mace, and one far below the entrance containing a Hellfire. However, the creatures you will encounter in the process of retrieving them will give you a good idea of what you're up against.  In particular, the Great Malboro and Abyss Worms are not to be taken lightly, with the amount of status ailments and full party attacks they can inflict.  The exit to the next floor can be found in the lower right corner.  Ignore all other doors.
 * Floor 2: There is a very high likelihood that you will be attacked by White Dragons as you explore this floor. Be prepared to counter with high level Fire spells.  Ignore all the doors on this level except for the exit in the upper right corner.  There are three chests, the first of which is directly above the entrance.  Open it for another Hellfire.  Then follow the water to the right, and after it heads down, check the short passage to the right for another chest containing Antarctic Winds.  But the best treasure of all can be found by heading down until you reach the bottom, and exploring to the left.  There you will find a chest containing the Cat Claw weapon (good for anyone who is experienced in fighting bare-handed), but it is guarded by a Blue Dragon.  Blue Dragon's specialty is Thunder-based attacks.  Therefore, its weakness is to Poison based attacks, so cast Scourge if you have it.  (The Blood Sword is also effective against this dragon.)  Then follow the bottom back to the right, and up the right side of the floor to find the exit.
 * Floor 3:This floor is fairly linear, and forces you to walk beneath waterfalls which sap a little of your health with each step beneath them. As is usually the case, ignore all the doors except for the very last door you reach in the lower left corner of the floor.  There is one treasure chest to collect along the way, and it contains the Rune Axe, but this powerful weapon is guarded by an equally powerful creature: the King Behemoth.  It's a more powerful version of the Behemoth you faced way back in the Coliseum.  It happens to be weak to Poison based attacks, but it's also weak against the Blood Sword, so it's a good idea to equip that weapon before you examine the chest.  The King Behemoth can land some incredibly powerful attacks, easily doing damage in the thousands to even very leveled characters.  Protect and Blink can go a long way to help you survive this battle, as can Haste and Berserk.
 * One thing to note before you leave this floor: if you examine behind the waterfall at the very bottom of the map, you'll discover an invisible salesman that actually sells some of the strongest Black magic in the game which can't be purchased anywhere else! You can buy a Death Tome or a Berserk Tome for 10,000 Gil each, Haste for 20,000 Gil, and Flare for 40,000 Gil.  Stock up if you have the money, and then proceed to the exit in the lower right corner.


 * Floor 4: There is a lot of important treasure to discover on this floor. Two can be found in chests out in the open, but three are behind a door found at the top of the room.  The first chest can be found on your way to the top, and contains a Betrayal Fang.  When you reach the door at the top, enter inside to find the Dragon Armor and the Aegis Sheild, two very strong defensive pieces of equipment, and the Holy Lance, a weapon you should consider giving to Leon.  Back outside, head to the right, and you'll find the second chest.  Inside, you'll find Yoichi's Bow, one of the best bows in the game, along with a forced fight against a Red Dragon.  As usual, the dragon is weak against the Blood Sword, and since its attacks are Fire based, it is also weak against Ice attacks, so cast Blizzard liberally.  When you are finished, proceed through the door in the lower right corner to access the next floor.
 * Floor 5: When you arrive on this floor, there is a sign posted by the entrance which informs you that the path you are on leads to hell (or some variation of that depending on which version you are playing.) Throughout this floor and the next, you will be attacked almost exclusively by Chimera Sphinxes, along with the occasional Green Dragon.  This floor is linear, and winds around a pit.  There are three chests along the way.  The first and last contain Hi Potions, but the middle chest near the top (ignore the nearby door) contains a Protect Ring, which increases a player's defense against instant-death magic.  Give this to any individual who is responsible for reviving fallen members of your party.  Then make your way around to the door in the lower left corner.
 * Floor 6: The final floor is barely a floor at all, containing just a small passage which leads you to a warp tile. This warp tile will transport your party into the Pandemonium fortress, the one which rose from the rubble of Palamecia when the Emperor returned.  Be advised: there is no turning back from this point.  If you took substantial damage from any of the forced fights, or find yourself lacking in any particular items, now is your last chance to Teleport out of the dungeon to heal and stock up.  Once you pass through the warp, that chance will disappear.

Pandaemonium
''Pandaemonium is the Greek for "all demons" ("pan"=all, "daemon"=demon)

Somehow, the enemies without a weakness are easier to defeat. Exploit the weaknesses of the others before they deal too much damage.

Random encounters (the number before the name is the enemy Rank):
 * R6 Coeurl:       no weakness;
 * R7 Devil wolf:   no weakness;
 * R7 Beast devil:  no weakness;
 * R7 Mantis devil: no weakness, absorbs Fire;
 * R6 Death rider:  weak against Fire; absorbs Death, but isn't weak against Holy;
 * R7 Mithril golem: weak against Lightning;
 * R7 Iron giant:   weak against Lightning and Ice, absorbs Fire.

Chest guardians:
 * R7 Zombie Borghen: weak against Fire and Holy, abosrbs Death
 * R7 Tiamat:        weak against Body (?), absorbs Fire, Ice, Lightning and Poison
 * R7 Beelzebub:     no weakness, absorbs Fire
 * R7 Astaroth:      no weakness

Item checklist:
 * G-floor: (no items)
 * Floor 1: ether
 * Floor 2: elixir
 * Floor 3: (no items; four doors to Floor 4 and 5)
 * Floor 4: Genji helm, Genji gloves, Masamune sword, Confuse tome dropped by enemies (no passages to floor 5)
 * Floor 5: Genji armor, ribbon
 * Floor 6: sage's wisdom
 * Floor 7: hellfire, acid phial
 * Floor 8: (no items)
 * Floor 9: (no items)

BOSS: the Emperor
He absorbs Matter element, that is any instant-defeat spell.

One effective strategy is to attack the Emperor with a Blood Sword, that will deal damage equal to 1/16th of the total HP of the target. Considering the fact that there are two Blood Swords in the game (NES and PS1 versions), and adding the damage dealt by other characters, the Emperor can be defeated in less than eight turns. In the GBA and PSP versions there is one Blood Sword only, so the fight will last twice as long.

An even more effective strategy is to cast high-level Berserk on a character equipped with the Sleep Blade and high-level sword skill: the Emperor will be put to sleep, he won't act at all and the combat can be easily concluded in just about four turns. Of course, once the Emperor is asleep, you can take it easy and test every attack and debuff spell on him, something like painting the face of a sleeping friend.