Resident Evil – The Mercenaries 3D: Unlock Signature Weapons
In Resident Evil: The Mercenaries 3D for the Nintendo 3DS, each character has signature weapons that can only be used by that character by default. Luckily, they made a way to make each character’s signature weapons unlockable for all other characters.
To unlock a character’s signature weapons, you need to get an SS rank in all missions in the game leading up to and including mission 5-5 with that character. Once you do this, that character’s signature weapons will be available for all other characters to use.