in arena chocobibi is able to multicast ultimate skill and bamboman will often not activate special regardless of autoplay or manual cast.
I can only show proof of bamboo as chocobibi only happens in defense
I’m my experience, Spear users (Kim and bamboo) on auto won’t use normal skill on 2 enemies when there’s another 2 on the team. So at least on pvp when there’s a team with 2 melee and 2 ranged, you should manually use skills. On defense this doesn’t seem to happen since I’ve used 2 melee 2 ranged and still see spear users attacking with all skills.