Some of the abilities seem like spells that focus on forged weapons.
This would need to be one, constant, length. Unless of course it's extending manually in terms of a rope which I doubt you want. Feel free to correct me.
The thorns can be on there but them launching would be a separate ability. It's too spell like (it is, however, a forge based spell).
The potential use for a boy by stiffening the whip is fine. And the only issue with the poison is that you don't specify what damage it does to the muscle tissue. What if it doesn't make contact with the muscle tissue and only hits the skin but doesn't break through all the way?