A seax is a viking weapon that can be used as a tool.
A knifr is a viking tool that can be used as a weapon.
A puukko is (probably) the descendant of the knifr.
A squirrel tail or blacksmith's knife has nothing to do with vikings.
A rail spike knife is an outstanding conversation piece.
A rail spike is not made of magical super-steel.
A kunai is a multi-purpose Japanese trowel.
A bo shuriken is a Japanese throwing spike.
'Ninja tools' were mostly just tools that you could carry without being executed for it.
Naruto is a dumpling.
The food item of the same name is also a dumpling.