User can control any blade around them.

Pros:
-user can cook well
-user can stop anyone getting hurt
-user can make assassinations quick

Cons:
-user will be seen with a knife on the often
-user will be unstable if not near a knife
-number of knives that the user can use varies

Weakness: fire
The knives will melt and the user will become unstable, almost animalistic as they fight and lose knives.