Tanto

Jin's short blade — the weapon the assassination animations are performed with, and the one that never appears in a duel.

The tanto is not a weapon you switch to. It is the knife Jin uses for assassinations and for the close, ugly work the katana is not for, and its presence in the game is almost entirely animation rather than mechanics.

That is itself the point: the katana is the weapon a samurai is seen with, and the tanto is the one that does the things a samurai is not supposed to do.

The assassination weapon rather than a duelling one — what Jin uses when he has decided not to announce himself.

Weapons and tools are improved through the skill trees, spending Technique Points earned as your Legend rank rises. Legend itself comes from tales — main and Mythic Tales give the largest steps, side tales, liberated settlements and cleared encounters the smaller ones.