Fire Chain

Fire Chains, also called Fire Bars, are spinning fireballs formed in a ring shape that originally appeared in the Mario Kart series. Similar to Fire Bars, Fire Chains serve as obstacles in all games in which they appear, and their rotating movement is similar to that of the Boo Buddies.

Mario Kart: Double Dash!!
Fire Chains first appear in Mario Kart: Double Dash!!. They appear in both Waluigi Stadium and Wario Colosseum alongside normal Fire Bars in the former, where they burn any racer that comes in contact with it and are made up of seven fireballs each.

Mario Kart DS
Fire Chains reappear in Mario Kart DS, where they are found in Wario Stadium. They play the same role of burning any racer who touch them, except they only have five fireballs each.

Mario Kart Wii
Fire Chains reappear in Mario Kart Wii, where they are found once again in, and in the game's Bowser's Castle where they are made up of three fireballs each.

Mario Kart 8 / Mario Kart 8 Deluxe
Fire Chains reappear in Mario Kart 8 and Mario Kart 8 Deluxe, where they only appear in. Here they are once again the main obstacle along with normal Fire Bars.

Super Mario Galaxy 2
Fire Chains also appear in Super Mario Galaxy 2. They appear in Bowser's Lava Lair, on the starting planet, and the fireball planet, and the Slipsand Galaxy on its starting planet. They behave the way they do in the Mario Kart games, though sometimes, they go around planets instead of circling in the air.

Super Mario Run
Fire Chains return in Super Mario Run, except with an appearance of a complete "ring of fire" rather than separate sets of fireballs. They appear only in the level Rings of Fire!.