FF12 Guide - Extreme Leveling

High Level Experience Points

source: FF12sector

This levels you extremely  quickly.  
I would recommend you be at least level 50 before attempting this 
one, but it's up to you how much of a risk you want to take.  

Teleport to the Jahara and enter the Lull of the Land area.  At the northeast 
corner you will find a Garif identified as Geomancer Yugelo.  You must have 
met the following conditions: completed the Hunt to defeat the Mindflayer, and 
second, you must have acquired at least 10 Espers.  

Assuming you have met these conditions, he will send a Garif warrior to open 
up the locked area in the Henne Mines.  That is your next destination.  
Teleport to the Henne Mines and head north, then east to reach the Phase 2 
Dig.  I would suggest looking down a little for the recommended Gambit setup, 
as it will help you not only at your destination, but on the way there was 
well (though you may want to keep Sleepga off until you get there and just use 
Curaja).

Make your way south through the Phase 2 Dig (there are paths leading down that 
don't appear on the map).  Eventually this will take you to Crossover C.  Head 
down to the southwest corner of Crossover C (watch out for the dangerous blob 
enemies, you may want to just flee there) and enter Pithead Junction C.  This 
is your main destination.

Pressing the switch in this junction will spawn more than a dozen of those 
powerful bats.  No doubt they would have very little trouble wiping out your 
entire party if given the chance, but a proper Gambit setup can tip the scales 
in your favour.  here's my personal favourite setup for this leveling trick:
========================
| Self: MP <> Charge
| Self -> Haste                          
| Ally: Any -> Arise
| Ally: HP <> Curaja
| Ally: Any -> Esunaga
| Foe: Undead -> Sleepga
| Foe: Undead -> Curaja
| Ally: Any -> Bubble
=======================

Also, make sure to equip everyone with the Embroidered Tippet (doubles EXP).

There are a few differences I suggest between the characters.  Your main tank 
should have the Self -> Decoy spell right above Sleepga (equip this character 
with a shield to hopefully block some of the bat attacks).  Another character 
should have Ally: Any -> Protectga (again to reduce damage).  Finally, I 
personally like to remove Foe: Any -> Sleepga from one character so that you 
are at least doing damage consistently even if one of the enemies refuses to 
fall asleep (I usually equip this character with Mystic armour so that the 
damage from his/her Curaja is as high as possible).

The basic idea is that the Sleepga spell will put all the bats to sleep 
(quickly).  The Curaja spell will do heavy damage to all the bats (since they 
are undead) and not wake them up (since it's Magick damage).  Bubble and 
Protect will help keep you alive until all the enemies are asleep.

Killing all of the enemies in here with the Enbroided Tippet equipped will net 
you more than 60000 EXP every single time.  Now all you have to do is press 
the switch again (no more spawns after the first press) to open the east door, 
head east to the Phase 2 Shaft, north to Crossover C, then turn around.  Since 
you just moved two screens you can now go back and press the switch again.  
The enemies will respawn.  Rinse and repeat this over and over and you'll 
reach the 80's in no time flat.