real easiest answer:shadow.why?

>shadow has got speed (38 base,2nd only to locke's 40)

so why not use locke?because of this.

>shadow can equip stunner (stop dagger) while locke cannot

btw,chupon is weak against stop.should the stunner trigger a stop (high probability) and you dont get too unlucky (shadow casts silence for 10 consecutive turns,for example),chupon will be down in no time at all.