Doctor Robotnik’s Flame Craft (フレイムモービル,Fureimu Mōbiru?, lit. "Flame Mobile") is the first regular boss in Sonic the Hedgehog 3. The player encounters it at the end of Angel Island Zone Act 2. It takes eight hits to be destroyed.
The Flame Craft is a vehicle piloted by Dr. Robotnik (or by EggRobo if the player is using Knuckles in the locked-on game), that can fly around in mid-air much like the Egg Mobile. Like Fire Breath, it is dark blue in color, bulky, and is fitted with two aim-able weapons on either side that shoot fireballs across the screen. It also has a small orange dome at the bottom of the mobile.
The Flame Craft first appears moments after Sonic and Tails outrun the bombs dropped by the Flying Battery. It flies past the player in the stage's background, before disappearing behind a huge waterfall. When Sonic crosses a wooden bridge, the Flame Craft emerges through the waterfall and drops a fireball on the bridge, destroying it. The player is able to fall into a bottomless pit if the playable character is standing on the bridge when it is destroyed.
The Flame Craft will then disappear behind the waterfall, becoming impossible for Sonic to hit, and emerge again in a new location to fire its weapons at Sonic again. Robotnik will move in certain patterns, either to the far right, upper left corner or left side. Robotnik will fire two fireballs each time it emerges, and Sonic will only be able to use the Spin Attack on it again during those times. After eight hits, the Flame Craft will be destroyed, and the floating Capsule will lower from the top of the screen. Opening the Capsule ends the level, after which the player will move on to Hydrocity Zone after Knuckles destroys the second bridge.
When playing as Knuckles in Sonic the Hedgehog 3 & Knuckles, the player enters the arena from a different pathway. EggRobo is seen piloting the vehicle using a similar pattern of attack, but is able to fire four fireballs at one time. After landing eight hits on the vehicle, opening the capsule and clearing the Zone, Knuckles will hop from the waterfall and the game will progress to Hydrocity Zone.
The Flame Craft has been featured in the French Sonic Adventures: Dans Les Griffes De Robotnik comic, where it is seen as Robotnik's main transportation vehicle instead of regular Egg Mobile. While not having the important role in the story, the arm cannons have motors behind them and function as flamethrowers instead of launching fireballs.
The Flame Craft appears on the US box art for the Sega Genesis version of Sonic the Hedgehog 3, but not on the box art for Mega Drive editions. Like in the French comic, Robotnik is seen firing flames instead of fireballs in the box art.
If the player is playing as Sonic and Tails and Sonic goes for the early hit when Robotnik destroys the bridge and gets Tails stuck behind the boss, Tails will bounce between the locked screen and the boss, defeating it within a few seconds.