Kodachi

Kodachi is a recurring weapon in the series, usually taking the form of a ninja knife or a katana. It is often a low-ranked weapon and provides no special abilities to the user.

Final Fantasy VI
Kodachi is a low-ranked dagger that can only be used by Shadow. It provides 82 attack, and is Shadow's initial equipment. Additional others can be stolen from Baalzephon.

Final Fantasy Tactics
Kodachi is a low-ranked ninja blade that provides 10 attack and 5% defense. It can be bought for 7000 Gil.

Dissidia Final Fantasy
Kodachi is oddly a level 22 armor that provides +1 Attack and +17 Defense.