The Pachisi Glitch can level up your characters fast:

To do the Pachisi Glitch, all you have to do is land on a ! or ? space on a Pachisi track and get a stat lowered by 1. Then, go into a battle and at the end of the battle you will get a ton of exp. and your character will grow a ton of levels.

This glitch can be done on the Pachisi Track in Kol.

I've tried to activate this glitch at level 23,
and never got it once. I spent 2 hours trying to
get it to work.

I got from level 23 to 47 on the Pachisi Track
by fighting normal battles, and did not encounter this
glitch at all. If someone could be more precise
on what to do, and give full detail on how
to activate it, that would really help. (By the way; I play on a GBA Emulator, and DWM3 Rom.)

the pachisi glitch is more of a random occurance and it can only happen to 3 confirmed classes the Hero, the sage, and the figher, during my 3rd play through as the hero on the pachisi track in kol (only one it works on) i encounterd a sky dragon and 4 meatly's which fled almost imeadiately but when i killed the sky dragon my hero leveled up to level 99 then i used my sage on the same track right after the hero was done and the same thing happened a single sky dragon and two derangers, which fled immeadiately then i killed the sky dragon and my sage went to level 99 i've tried it with every other class but the only other class that has worked was the fighter in the kol track vs a single sky dragon which is more of a random occurance than an actual glitch than can easily be repeated