Popgun

The popgun is a pistol weapon used by the Kongs in the Donkey Kong franchise. They are small, ranged weapons which shoot various types of projectiles. Since Donkey Kong 64, a pair of popguns have been Diddy Kong's signature weapon, more specifically the Peanut Popguns, which shoot out peanuts. The Peanut Popguns are two wooden pistols which appear to be hollowed out logs.

Donkey Kong 64
In Donkey Kong 64, Diddy can buy the Peanut Popguns from Funky's Store as early as Jungle Japes for three Banana Bunch Coins. Like the other Kongs' weapons, Diddy uses the Peanut Popguns for various reasons, such as shooting enemies, Peanut Switches, and red Banana Balloons. In Jungle Japes, Diddy must use the Peanut Popguns to shoot three Peanut Switches, each one opening a gate in a different part of the level.

When Diddy is using the Rocketbarrel Boost move, he is always holding out his Peanut Popguns. When Diddy is on land, the player must simultaneously press and  for him to take out the Peanut Popguns, or another time for Diddy to put them away.

Starting with Fungi Forest, the Kongs can go to Funky's Store to buy an upgrade for five Banana Bunch Coins that enables every Kong's personal weapon, including the Peanut Popguns, to use homing ammo that they pick up from red Supply Crates.

Donkey Kong Country Returns / Donkey Kong Country Returns 3D
The Peanut Popguns make their Donkey Kong Country series debut in Donkey Kong Country Returns and its Nintendo 3DS port, Donkey Kong Country Returns 3D. They have a stubbier appearance and are each held together by two iron rings. Diddy can use them by default, although they are less effective than in Donkey Kong 64 and can only be used in 2-player mode, where Diddy is independently controlled by the second player. With the Peanut Popguns, Diddy can perform the Popgun Pound ability, where he shoots peanuts while ground pounding. Alternatively, Diddy can shoot peanuts if the second player shakes the Wii Remote while Diddy is in mid-air or if he is on Donkey Kong. Launched peanuts bounce on the ground quickly and break upon hitting a wall or an enemy, and Diddy can temporarily stun most enemies by shooting peanuts at it, briefly causing it to become dizzy or confused. Bosses and certain enemies such as Tikis are not affected by the Peanut Popguns's projectiles.

In the respective boss fights for Mugly and Thugly, when the boss opens its mouth, Diddy can optionally shoot peanuts into it. By shooting enough peanuts, the boss temporarily stops to chew on the peanuts, and its vulnerable spot is exposed. This is indicated by hearts surrounding their head. After taking a hit, the boss stops being distracted and continues with trying to attack Donkey Kong and Diddy Kong.

Donkey Kong Country: Tropical Freeze
The Peanut Popgun returns as Diddy Kong's weapon in Donkey Kong Country: Tropical Freeze, appearing alongside the Gumball Popgun and the Denture Popgun, used by Dixie Kong and Cranky Kong respectively. The new popguns have the same usage as the Peanut Popguns, and can all be used as in Donkey Kong Country Returns. The player can use popguns whenever Diddy, Dixie, or Cranky are controlled independently, which is possible in multiplayer sessions and in Hard Mode. In order to shoot the weapon, the players that control these characters have to press the ground pound button while in mid-air or mounted on the character the first player in multiplayer controls (Donkey Kong or, exclusively in the Nintendo Switch version, Funky Kong). Like the previous game, Diddy can feed some bosses by shooting peanuts into their mouth.

Dixie Kong's popgun shoots bubblegum instead of peanuts, which is a reference to Dixie's idle animation in Donkey Kong Country 2: Diddy's Kong Quest and Donkey Kong Country 3: Dixie Kong's Double Trouble!, where she would blow bubblegum. Cranky Kong shoots, alluding to his old age, although his alleged popgun is never shown.

Super Smash Bros. series
Diddy Kong's standard special move in Super Smash Bros. Brawl, Super Smash Bros. for Nintendo 3DS / Wii U and Super Smash Bros. Ultimate involves using a Peanut Popgun, and can be charged up. The popguns are fully charged when Diddy reaches up and grabs his hat. When charged up, the peanuts fired are much faster, and will have a better chance at hitting the opponents. If Diddy charges it for too long, the popgun explodes in his hands, briefly stunning him but otherwise not dealing any damage. Diddy Kong uses his Peanut Popguns during his Final Smash, the Rocketbarrel Barrage.

In Super Smash Bros. Brawl's The Subspace Emissary, Diddy uses the Peanut Popguns in two cutscenes to attack enemies. In one cutscene, when Donkey Kong and fight off the Koopa Troop, Diddy blasts the Bullet Bills with peanuts, posing with Donkey Kong as one of the defeated Bullet Bills explodes behind them. In a later cutscene, when Diddy is dropped out of the Arwing, he propels himself up to the Smash Skiff, blasting the Primids with peanuts.

In Super Smash Bros. for Nintendo 3DS / Wii U, the explosion can also damage opponents. The Peanut Popguns occasionally releases peanuts that can be eaten as food. If Diddy Kong's powers are copied by Kirby, he will also be able to use Peanut Popgun. In Super Smash Bros. for Nintendo 3DS / Wii U, this move has two custom variants: Exploding Popgun, which does not fire peanuts and can only deal damage by exploding, doing it more quickly; and Jumbo Peanuts, which fires larger peanuts that do not travel as far and deal more damage.

Dr. Mario World
In Dr. Mario World, Diddy Kong uses a Peanut Popgun for his special ability, which splits each Megavitamin in two and allows for each part to be placed individually. To indicate the splitting, a peanut breaks in half when the ability is activated.

Trivia

 * A pre-release screenshot of Donkey Kong 64 shows that the Peanut Popguns were conceived as weapons similar to realistic pistols.
 * Diddy Kong's association with the Peanut Popguns is referenced in his bio on the Super Mario Party official website, where he is described as a "peanut-popping powerhouse."