This is a question my former therapist had asked me years ago. I didn't have an answer.
I was thinking about it today and, of course, my mind shifted to ATLA instead.
Then I thought... what fuels the characters?
Open to discussions but not arguments.
Ty Lee:
Self-preservation.
Master Piandao:
Excellence.
June the bounty hunter:
Profit.
Firelord Ozai:
Dominance.
Wan Shi Tong:
Preservation.
Gran Gran Kanna:
Resilience.
Lieutenant Jee:
Solidarity.
The Mechanist:
Innovation.
Guru Pathik:
Enlightenment
Avatar Yangchen:
Pragmatism.
Avatar Kyoshi:
Enforcement.
Professor Zei:
Reverence.
Koh the Face Stealer:
Spite.
The other Fire Sages (Corrupted):
Opportunism.
The Cabbage Merchant:
mY cABbAGeS!