Differences between 征, 伐, 讨, 侵, 袭?
it is hard to tell what they exactly mean without contexts, but i can give you a very general idea of these characters:

征 (zheng1) means 'wage war by travelling a long distance'. it is usually associated with a war with a very large scale in both space and time.

伐 (fa2) is just 'to wage war against', nothing more. in fact, among all five characters, only the original meaning of 伐 is directly related with war.

讨 (tao3), literally "to demand", means "to wage war demanding justice/punish the wrongdoers"

侵 (qin1) means “to invade" or "to encroach"

袭 (xi2) is usually associated with “sudden attack”.