@Scio Malice-filled, I guess.
In terms of the dog, because it's made of shadow, it can phase through solid objects, and also project shadow onto other locations and beings. It would be killable though, to keep it not so OP. It obeys the character's every command and requires no liquid or solid sustenance.
In terms of iron manipulation, he can control objects and entities which contain large amounts of iron atoms. Like, he can move them around with his hand. However, as I mentioned before, he can only control small to medium sized objects, because he uses the iron atoms in his own body, so if he tries to control something too large, or too many things at once, the amount of iron atoms in his own blood explodes, causing severe damage to his heart and liver, which would lead to death eventually.