RNG Guide

Kikuichimonji is the only Rare Item Drop that can be obtained by manipulating the RNG 100% of the time in either game. It is a pretty good weapon, and is Ivan’s ultimate in the first game.

There are several conditions that must be met:
Your attack order must be: Ivan, Mia, Isaac, Garet
All of them must have above 150 for their agility stat.
You must have all 28 Djinn, and each of them must be set (white font, not red) on their respective adept (Venus Djinn on Isaac, Jupiter on Ivan, etc.)

Save the game in the first room in the Venus Lighthouse, the one with the psynergy crystal.

Turn OFF your GBA system. You must physically move the switch; a soft reset (A+B+Select+Start) will not work.
Turn your Gameboy back on. Run around the room until you get into a battle, it should be a Fenrir and an Ice Gargoyle. There is a slight chance the enemy may attack first, if this is the case turn off your Gameboy and try again.

The Battle:

Turn One:

Ivan casts Tornado, big arrow on Fenrir Mia casts Tundra, big arrow on Fenrir Isaac casts Earthquake, big arrow on Fenrir Garet casts Flare Wall. Fenrir should still be alive by the end of the turn. (Note: If you're levels are too high, the above psyenergy may kill Fenrir. If this is the case, just use weaker psyenergy of the same Element.)

Turn Two:

Ivan defends Mia casts any form of Wish Isaac defends Garet unleashes Torch on Fenrir Fenrir should now die, after flashing strange colors and making a different dying screech.

Turn Three:

It really doesn’t matter how you dispatch the Ice Gargoyle, so long as you don’t unleash any more Djinn. If you really can’t think of anything, here’s a suggestion: Ivan uses Weapon Attack on Ice Gargoyle Mia uses Weapon Attack on Ice Gargoyle Isaac uses Weapon Attack on Ice Gargoyle Garet uses Weapon Attack on Ice Gargoyle

After the Ice Gargoyle is dead, you should get some experience, some money, and the Kikuichimonji.

These are the rest of the Rare Item Drops you get and what monsters you get them from. Try experimenting with the method above on these monsters.

Giant Axe- Dropped by Earth Golem (Venus Lighthouse)
Blessed Mace- Dropped by Thunder Lizard (Venus Lighthouse)
Zodiac Wand- Dropped by Grand Golem (Venus Lighthouse)
Prophets Hat- Dropped by Dread Hound (Altmiller Cave)
Aura Gloves- Dropped by Magicore (Suhalla Desert)
Feathered Robe- Dropped by Wild Gryphon (Venus Lighthouse)
Spiked Armor- Dropped by Chimera Mage (Venus Lighthouse)

I’m very sorry that I can’t tell you of a 100% way to get any of those above. About a year of off and on experimenting proved to me that none of the others are set past a certain point like the Kikuichimonji. I got excited at one point, thinking I had found a sure-fire way to get the Feathered Robe, but the fifth time it worked, one of my party grew a level and it did not work the sixth. So you’ll just have to figure it out yourself, if you can’t just leave it up to chance, as the game designers had in mind.