For those whom want to get all the different endings but can not figure out how here is a list of what to do to get them. Hope it helps.

http://db.gamefaqs.com/computer/doswin/file/guilty_gear_xx_reload_pc_story.txt

Dizzy's last path is a nightmare. God damn it.

only started it today but made sure to look on gamefaqs for how to get the different paths, loving it so far (only done its with Sol and Ky, paths 1 + 2 for each), and dear god is Robo-Ky evil in Path 2, eventually did it with an instant kill finally not being blocked

ill also add the fight afainst slayer in Millia's story to the annoying fights list

If you did not like that one your not going to like fighting him as venom. In that fight instant kill is your friend. (if you can get it to hit that is)

instant kill was definitely my friend, done story paths 1+2 with all but 3 people now, then i'll start on story path 3

Are certain characters supposed to be invulnerable or regenerating? Slayer's first path final was Zato who had half a bar of health that never budged, and the third path final was I-No who was regenerating?

Yes. In story mode some characters do regenerate, or are invulnerable to certain attacks. Some need to be hit with a tension attack to be damaged (rob-Ky) others can only be harmed by special moves, and once and a while can only be harmed by normal attacks.

Instant Kill will however work on all or almost all at least

AS for the instant kill I really wish Dizzy had one in this game. Sure her tension attack is powerful, but half the time the damn attack only does %30-50 damage.

Note I only want it for the I-no fight. Other than that couldn't care.