-Edward, Leonardo, Sothe, Sigrun, Sanaki, Zihark, Mia, Micaiah, and Mist have both good skill and luck (aka Accuracy).
-Edward, Leonardo, Zihark, and Mia get a +20 (+15 for Leonardo) crit bonus.
-Edward/Mia + Light Affinity Support Bonus + Killing Edge + 20 crit bonus + Gamble = Win (Although they probably wouldn't need gamble because they are both awesome without it)
Don't kill me.
Kieran really fails with gamble because he lacks the accuracy and crit bonuses that really make it awesome.