For use in a system where random rolls are a thing.
[b]Four Sided Die[/b]
When used, it grants the player a buff titled "Lucky Number" followed by a random number between 1 and 4.
The Player uses the consumable and gets the buff "Lucky Number 2", and heads into a strike. This strike in particular has a chance to drop a hand cannon at the end. Player already has one, but wants better perks. He likes the perks in column 2 of his current hand cannon, but hates the others.
Player beats the strike with the Hand Cannon equipped. The buff Lucky Number 2 senses two things:
1) Player is holding (Hand Cannon).
2) Activity has chance of dropping (Hand Cannon).
Lucky Number 2 then drastically increases the chance of the player receiving another of the same Hand Cannon. If it doesn't drop, the perk doesn't go away, and the player can try again. If a Hand Cannon does drop, then Lucky Number 2 does something else as well. The perks in the Second Column of the new HC will exactly match the perks in the Second Column of the HC the player has equipped.
To summarize, using this consumable increases your chance of receiving a duplicate of one of your equipped weapons from an activity if it can drop there already, and guarantees one of the columns will exactly match the perks in the one you already have. The buff the consumable provides will stay active until it succeeds in providing you with a duplicate, at which point it'll expire.
As for how Four Sided Die will be obtained, I'm thinking similarly to Three of Coins.