It's appearances in games
Mario Kart 8
Oil Barrel is Baby Walice's special item. She uses the item to throw an oil puddle on the floor and people who go across the pool will slip.
It also appears in Mario Kart Rush.
The Oil Barrel appears as a new item in Mario Kart Silver. In the game, it is a common item, and can be obtained in first, second, third, fourth, fifth or sixth. When used, the barrel bounces on the ground, creating an oil slick, before disappearing. The oil slicks act the same as they do in Super Mario Kart, as they make the racer spin out. Unlike in Super Mario Kart, however, hitting an oil slick will cause oil to splash up on the racer, which (should it be a player) act similarly to a Blooper, though with more visibility. The oil slick will also disappear once hit.