All 6 HEIYU sales people
After you unlock Funbari Shopping Town, go right to the HEIYU building. Speak to the HEIYU salesperson. When he asks you for service, say yes. Then another spirit will appear. Tell him you want service also. This will repeat itself until the sixth one says that you are too greedy. Then a fight starts. You will battle HEIYU salespeople 1-6. Beat them and you will get to have all of them. You can use all of them in one party to exploit every spirits weakness since they are all different types. Note: Swap the HEIYU sales person whose type is light with Amidamaru after Amidamaru learns Grand Halo Blade.
Spirit Combinations
Ant + Guardian Spirit - Garuda
Fore Fiend + Uriel - Pascal Avaf
Garuda + Shaolin - Giant Eliza
Guardian Spirit + Calvary Statue - Teammate
Giant Eliza + Grand Tao King - Corey
Mosuke + Shaolin - Tokageroh
Metatoron + Guardian Spirit - Joto No.1
Mosuke + Yamatano Orochi - Lee Pai-Long
Shaolin + Torture Twin #2 - Silver Wing
Tokageroh + Torture Twin #2 - Shion Shion
Teammate + Teammate - Grand Tao King
Uriel + Metatoron - Mosuke