After beating The Big Bang Colosseum tournament, you will qualify for the Zodiac Monsters. These monsters are special breeds that you first must encounter with an event. These events occur in various places and there is one event each month.

Month	Place	Monster	Code	Notes
1	Papass Mountains	Z (Durahan/?)	Code	Find the Builder in the upper right area of the map. Afterwards, go a little further north to find a Durahan. Defeat him for the code.
2	Volco Lava	Blue Phoenix (Phoenix/?)	Code	Find Cammy around the first bend. Follow the road further until you reach the place where you helped the first phoenix. Fight the Phoenix there for the code. WARNING - This Phoenix has 1500 life!!!
3	Promiass	Ultimate (Gali/?)	Code	Find Ron at the event crystal up the first north hallway. Then head Right to the middle of the three possible hallways. Meet up with the Gali. Fight him for the code.
4	Jungle	Sonna Banana (Naga/?)	Code	Find Cammy at a crystal immediately south of the pond. Break through the log in the southeast corner and find the Naga in that loop. Fight him for the code.
5	Promiass	Caesar (Xenon/?)	Code	Find Crysta at the mouth of the hallway where you got the King's Crest (In the central area). Head toward the same room as the King's Crest. At the entrance, the Xenon will appear. Fight him for the code.
6	Angowass Road	Beretta (Joker/?)	Code	Find Amino and his assitant just off the road between the two bridges. Head up the river (but not across the second bridge) to encounter the Joker. Fight him for the code.
7	Jungle	Killer General (Zan/?)	Code	Find Colt at an event crystal in the upper left area. After, you will get another event crystal nearby where you encounter the Zan. Defeat the Zan and you will be given the code to generate the Killer General.
8	Beach	Eggplantern (Beaklon/?)	Code	Find Tora at an event crystal in the area to right of the top of the map. After finding him, head directly to the right toward the plaque. You will encounter a Beaklon. Defeat him to get the code.
9	Volco Lava	Vega (Dragon/?)	Code	Find Ron at Event Crystal in second ring above center. Go all the way to the center to find the Dragon. Defeat it to get the code.
10	Papass Mountains	Kenjirou (Cantaur/?)	Code	Find the Centaur between the point of the L crack and the center butte. He looks like Kentaro, but is a different monster. Defeat him for the code.
11	Angowass Road	Akashic (Monol/?)	Code	Find the event crystal just above the road between the 2 bridges. Fight the Monol the get the code.
12	Farm	Proto Zero (Henger/?)	Code	Go to the gate of your farm. Roroi will show up at an event crystal where the road begins. After talking to him, continue up to the very end where the gate is. Fight the Henger there.