There is one in the Sages tower

one in the desert in the dunes called anubis and white tiger is on the way to the sages tower in the caves...still looking for the last one...

oh wait... its in the dream state that the sage puts you in... cant find the other one yet tho..

one is in the dream with the sage one is in the desert and one is where you go down to go back to yokohama and the bridge is out well go down like your going into the water and instead of going into the water keep going farther along side the river and its back in there hope it helps

Theres Anubis, in the desert near junk city, just fall in that hole in the ground, hes dark so bring some light golems.

Black Dragon, near yokohama, also dark and fairly easy to defeat as long as you stay away from the x-cutter

Gold squat, hes light, youll find him at the top of the sages tower just before you fight odin

Then that last one whos name i could never remember nor pronounce ;P, hes in your head when the sage sends you there. hes a tough one, i beat him cause i had wide range which lets you move to any space in your territory, so you can back up, heal and hell move up to attack you, then do a rush on him

The one on the way to yokohama is under the blown up bridge to the left of the second entrance to the river that you must swim across to reach yokohama.