Bat the Night Mage. She is the 12th of the "Tails" that are playable. She is efficient is at flinging curses and debuffs from afar and is well-trained in dark arts. She can also create doppelganger to confuse foes and can be equipped with life draining abilities. There are two "Routes" that she can learn skills from, the Shadow Caller (Route A) and the Dream Caster (Route B).
The nocturnal mage of darkness, she specializes in debuffs.
The illusionist of dreams. She can use her power to create shades to confuse enemies and can also learn a variety of debuffs.
Attack: Although Attack determines the amount of damage inflicted on Drain Life, The damage of Drain Life cannot exceed the cap of the max damage (9,18,27 dmg). However, if you have Shadow Illusion, Doppergangers also do damage based on your attacks. You might add some points here to increase normal damage.
Defense: Being a magic caster means you don't have much Defense and Vitality to begin with. Defense and Vitality can help you survive to inflict more debuffs. Vitality however seems to do better in defensive style.
Agility: With many Agility, skills have less cooldown so you can use the skills with less gap. However, you might want to keep an eye on your MP.
Vitality:As said in Defense, Magic casters are quite vulnerable. Invest some points here to survive longer.
Intelligence: Intelligence is important as Bat's skills use MP, if you have lots of Intelligence you can cast many spells to debuff or confuse foes. It also reduces spell cast time so you can use much more skill in continuation.
Talent: Talent's not much of important as Bat's skills focuses on debuffs. Only few skills like Dream Dazzle, Phantasm Blast, Echoes need Talent to boost the damage of the skill.
Luck: Luck's only useful for Charm as Luck affects the chance of the move that has the chance of occuring, Charm is the only move with that properties. Luck also affects Auto Mass, but Auto Mass is quite late to achieve as it is the fourth of the basic addition of C-skill tree.