Skill, Technique
You can branch out your fingers. It's your special skill that requires some good techniques. Your fingers branch out into smaller fingers and you can hold things really well. You can type super-duper fast. And you can win any tickle fight. These are skills you have thanks to your branching fingers.
If you could have any skill imaginable, what would it be? Wouldn't it be nice to have these magical branching fingers? (Definitely. It would.)
ぎ
わざ
None
Unfortunately, these skills are too much for the normal skill-less people to handle and they pull out the guillotine (ぎ). I guess they're going to chop off your skillful fingers because they're kinda scary.
Imagine a tiny guillotine made for the cutting of fingers. Whoever made this must have had special hand skills too! Maybe they tested it on them...