Props for attempting this! I would suggest throwing in the Lawful/Chaotic axis as well since it allows for added nuance. In the meantime...
Champs you have listed as Good that I think should change:
Akali, Kennen, Shen: Their order is all about balance. Neutral.
Caityln, Fiora, Wukong: Caitlyn and Fiora seem mostly motivated by dilettantism and a desire to improve their skills, so I'd call them as Neutral. Wukong is similarly interested just in becoming a better martial artist.
Master Yi: He has too much vengeance in his soul, I think, to be classified as good. Neutral seems more appropriate.
Shyvana, Sona: They strike me as someone moral-neutral.
Vayne: I dunno about Vayne. Her quest is a bit too bloodthirsty and hate-centric, but Neutral doesn't seem to do her justice and Evil seems too harsh.
Champs you have listed as Neutral that I think should change:
Evelynn: her title is "the widowmaker." I'm pretty sure she's ebil.
Ryze: He might be Good, actually. He started out just seeking knowledge and magical power, but now he has something of a save-the-world mission in protecting his scroll.
Sivir: She kills for gold, so I'd probably list her as evil.
Twisted Fate: He sold his best friend and partner-in-crime for magical power. Evil.
Varus: Evil, with the potential to quickly become good.
Vladimir: Evil evil evil. He's a murderous sociopath who pursued blood magic so he could murder better.
Xerath: You know, I really, really want to say he's Evil, but I just can't be sure?
Champs you have listed as Evil that I think should change:
Darius: Just because he KSes all the time doesn't mean he's evil. ;P
Diana: I really just don't know about her. I think I'd still keep her as Evil, but (like Varus) can change to Good in an instant.
Kog'Maw: I think I'd actually list him as Neutral. He's amoral, not immoral. A destructive force that kills people, obviously, but he doesn't seem especially cognizant of what he's doing.
Viktor: Maaaaaaybe. I'm not so certain. Seems more Neutral-but-could-become-evil to me.
Fizz, Nidalee, Orianna, Rammus: Neutral.
Gangplank: So very, very evil.
Maokai: Probably neutral.
Ms. Fortune: Probably good (pirate hunter).
Mordekaiser: Who knows?
Nautilus: Evil. He's a creature of vengeance and hatred now.
Riven: I would actually say Good. Possibly neutral, but probably Good.
Trundle: Good, decidedly.
Zyra: From her in-game VO, I'd say Evil.
Gangplank I would go with Chaotic Neutral or Lawful Evil. He has standards and wants to help Bilgewater, but he's still a pirate.
Fizz I would put as Chaotic Good or Neutral Good. He saved Bilgewater, but he's quite the prankster, and seems like quite the brutal fighter.
Hecarim is most certainly Chaotic evil considering he MASSACRED a demacian regiment and anyone that got in his way.
Maokai is Chaotic Good. He recognizes the misuse of magic and has standards,and I mean like he wouldn't randomly murder people, but he really, really hates magic users and those who abuse magic.
Miss Fortune is probably Lawful Neutral. She's out for herself, but she hates pirates and also wants to keep the waters free of em.
Mordekaiser..... I dunno. The quote at the end of his lore mentions that his suit may be keeping the world safe from him. He is obsessed with death and plague, kills people by touching them, and explodes into a noxious cloud when he dies. I think he may have joined the League to get rid of whatever is plaguing him.
Nautilus is Chaotic Neutral. He just wants revenge on certain people, but he isn't evil.
Nidalee is True Neutral. Representing herself and only herself. Maybe Chaotic Neutral considering she has killed people who trespassed on her domain before.
Orianna is bizarre to place, so I shall put her as True Neutral. She tries to please her father, and would just as soon save children from a burning orphanage as light the damn place on fire. Whatever makes her father happy.
Rammus is Lawful Neutral I see him as. He isn't a mean guy, but he doesn't have much to say and doesn't do much.
Riven is Lawful Good, and see's the error of her ways and wishes to atone.
Sejuani is Lawful Evil. She wants to rule and conquer Freljord by killing Ashe and Lissandra. However the Freljord of her vision is probably quite the brutal place. She wouldn't randomly massacre outsiders, but may attack Ashe's people.
Trundle is somewhere within the Neutral stage. He wants himself cured, but purposefully denied his kind the cure that would safe them out of revenge. He does what he wants basically, but he isn't evil. He also is probably quite lonely, kinda like Amumu.
Twitch is insane, legitimately, and may be responsible for a rat infestation. He's not the "nice guy" insane either. Chaotic Evil or Neutral Evil.
Zyra I see as Chaotic Neutral. She follows her instincts, but these harm others. She probably doesn't know what "evil" is.
I'm not sure if Lulu should be listed as "good". She's quite neutral if you ask me, she WAS banned from Bandle City after all, which is not the easiest thing to manage. She is not evil, nor good. She may seem sweet, but she has fairly low regard for how others think, as was seen when she was "playing" with Yordle children and turned them into flowers.
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