Fire Bar

Fire Bars (also parsed Firebars ) are rotating rods made of fireballs first appearing in Super Mario Bros. They are found in numerous titles throughout the Mario series. They are generally found in fortresses and act as dangerous obstacles that Mario must avoid in order to reach the goal.

Fire Bars were also given notable appearances in certain castles of Super Mario World 2: Yoshi's Island, which depicted them as swinging three-dimensionally. A three-dimensional Fire Bar depicted with eyes also appeared in Waluigi Stadium and Bowser's Castle course of Mario Kart: Double Dash!!

Super Mario Bros.
Fire Bars make their debut in Super Mario Bros. Although they are not a living enemy, they are more as an obstacle as they rotate around a block in a clockwise or counter-clockwise direction. They often appear on the ceiling and floors of castles. If Mario or Luigi makes contact with one he will take damage from the fire. In later games, they are replaced with similar-acting obstacles such as Roto-Discs and Ball 'n' Chains.

Super Mario Bros.: The Lost Levels
Fire Bars also appear in Super Mario Bros.: The Lost Levels. As in Super Mario Bros., they spin around in a similar fashion. In some castles, there are huge Fire Bars with at least 14 Fireballs, unlike the normal Fire Bars, which usually have 6 fireballs.

Super Mario 64
After an absence in Super Mario Bros. 3, in Super Mario 64, they appear for the first time in full 3D. They only appear in Lethal Lava Land. Unlike Fire Bars' 2D appearances, here they spin horizontally. Also different from their 2D appearances, there can be more than one Fire Bar rotating on the same axis.

New Super Mario Bros.
In New Super Mario Bros., Fire Bars first appear in World 6-4. They also appear in the second tower of World 8, and a lone one appears in Bowser's Castle. Here they act just like they do in Super Mario Bros., but are found more commonly more on the ceiling and floors.

Super Mario Galaxy
In Super Mario Galaxy, they appear as obstacles in a number of different galaxies, including the Sling Pod Galaxy, the Toy Time Galaxy, Bowser's Star Reactor, and Bowser's Galaxy Reactor.

New Super Mario Bros. Wii
In New Super Mario Bros. Wii, Fire Bars only appear in the tower and castle of World 8. In the tower, many are seen and one is guarding a Star Coin. There is even a double Fire Bar that has two rods of fire sticking out of the block. A secret room also houses a Star Coin guarded by 3 Fire Bars. In the castle, they are mainly seen in the first room, and only two are seen in the second room, one is even guarding another Star Coin.

Super Mario Galaxy 2
In Super Mario Galaxy 2, the Fire Bars' function is the same as in Super Mario Galaxy. They mainly appear in Bowser Jr.'s Fiery Flotilla, Bowser's Gravity Gauntlet, the Slipsand Galaxy, and Bowser's Galaxy Generator. It is also of note that rotating Fire Bars are used during the boss battle with Bowser Jr.'s Boomsday Machine in Bowser Jr.'s Boom Bunker, where they are integrated directly into the Boomsday Machine.

Super Mario 3D Land
Fire Bars reappear in Super Mario 3D Land. Here, they appear in most castles and then the level before Bowser's Castle. As with all 3D Mario games, these Fire Bars spin horizontally. This game also introduces Spike Bars, which are essentially duplicates of Fire Bars with spiky properties.

New Super Mario Bros. 2
Fire Bars appear again in New Super Mario Bros. 2. They have the same strategy from both predecessors and may also sometimes hide Star Coins. Fire Bars only seem to be one fire ball longer then past games. They mostly appear in castle levels and sometimes World six levels.

New Super Mario Bros. U
In New Super Mario Bros. U, Fire Bars appear once more and have a whole level based around them in Superstar Road called Fire Bar Cliffs which is home to countless Fire Bars of gigantic size. These huge Fire Bars also appear in the Meringue Clouds fortress.

Super Mario 3D World
Fire Bars appear in the game Super Mario 3D World. This time some of them rotate around Brick Blocks and Question Blocks. Spike Bars also return with a new appearance.

Yoshi series
Fire Bars appear in Super Mario World 2: Yoshi's Island and its remake Yoshi's Island: Super Mario Advance 3. They appear in certain forts and castles. They are usually depicted as swinging three-dimensionally. They also reappear in Yoshi's Island DS.

Mario Kart series
Fire Bars make several appearances in the Mario Kart series. Fire Bar rings make their first appearance in Mario Kart: Double Dash!!, where they appear on the Waluigi Stadium and Wario Colosseum courses. Fire Bars later return in Mario Kart DS, in the Wario Stadium course. Here the Fire Bars have both ring and "Y" forms. Fire Bars reappear once again in Mario Kart Wii, in the Waluigi Stadium retro course and the game's Bowser's Castle. Additionally, Fire Bars make reappearances in Mario Kart 8's Bowser's Castle course and in the Mario Kart DS Wario Stadium retro course. Here the Fire Bars have the same forms as in Mario Kart DS.

Paper Mario
In Paper Mario, the Fire Bars reappear in Koopa Bros. Fortress and Mt. Lavalava; this time they swing sideways. They also swing either clockwise or counter-clockwise. If Mario touches one, he loses some HP, but if Mario's partner touches one, nothing happens. Jumping over one of these Fire Bars causes it to swing faster. If Mario dodges one ten times, it will vanish and drop a number of coins. This is the first appearance in which Fire Bars can be destroyed.

Paper Mario: The Thousand-Year Door
In Paper Mario: The Thousand-Year Door, they reappear in Bowser's third platform level. Here, they can be defeated by Bowser's firebreath. If Bowser come in contact with the fireballs, they can either decrease his size or defeat him (if he's tiny). They also appear in the Palace of Shadow and have the same behavior as they do in Paper Mario.

Super Paper Mario
Fire Bars reappear in Super Paper Mario. In the game, they act in a similar fashion as in Super Mario Bros. and appear in Chapter 1-4 and 8-2. Mario can flip into 3-D mode to avoid the Fire Bars.

Mario Party 4
Fire Bars also appear in Mario Party 4. They only appear in The Final Battle!, they take away a heart from the player if it's touched.

Mario Party: Island Tour
In Mario Party: Island Tour, Fire Bars appear in the minigame Great Bars of Fire.

Super Smash Bros. for Nintendo 3DS / Wii U
In Super Smash Bros. for Nintendo 3DS / Wii U, Fire Bars appear as an item. Once picked up, characters can attack others by swinging them, similar to the Beam Sword. However, every two hits from a Fire Bar causes it to lose a fireball, shortening it in length and range.

Super Mario Maker
Fire Bars are set to reappear in Super Mario Maker.

Trivia

 * According to Satoru Iwata, "...firebars, which appear in Super Mario Bros., had also been used early on in development of The Legend of Zelda..." They did not appear in the final game, but the concept was reused as the Guruguru Bar in The Legend of Zelda: A Link to the Past.
 * Fire Bars are the only obstacles in Super Mario Bros. not to return in Super Mario Bros. 3, being replaced by the similar obstacles Roto-discs instead.