In the beginning, the Mogu Knife was Josh's best weapon. It is a simple knife, but it is dull-proof and is sharp enough to cut nearly anything straight through. Due to my lack of drawing skills back then, it is a handle with a triangular blade. It was replaced by the Alpha Blade.
The Mogu Knife's story is that it was given out to the champion of the "Mogu Brothers" tournament. Jake Ace came in second in that competition, and got to know Josh through that.