Balloon Boy

BB becomes active on Night 2. Starting in the Game Area, he will eventually come to the Office via the Left Air Vent. With each of his movements, he can say, "Hello," "Hi," or simply laugh. BB will not show up on any cameras except the Game Area and the Left Air Vent, keeping his path of approach hidden.

Balloon Boy is the only animatronic in the game that will not kill the night guard, but rather he will make an annoyance of himself by disabling the Flashlight and Air Vent Lights all while a sound loop of him laughing will play until the player is killed or gets to 6 AM. If this occurs, the player is especially vulnerable to Foxy's attack, as he can no longer be stunned with the now disabled Flashlight. To prevent Balloon Boy from fully entering the office, the player must put the Freddy Mask on while BB is in the Left Air Vent, and wait for the sound cue that he has exited the vent. However, the player should be advised that the noise heard may possible be another animatronic entering or exiting the Office or vents. Once BB has left the vent, he will return to the Game Area, and his cycle will repeat. If the player instead pulls up the monitor while BB is still in the vent, he will enter the Office. Balloon Boy will remain in the Office for the rest of the night, rendering it nearly impossible to beat unless it is close enough to 6 AM or Foxy's AI is set to 0 on the Custom Night.

While not appearing as an animatronic, Balloon Boy's image is used in the play testing of Gravity Vortexas well as Lemonade Clown and Fruit Punch Clown.

BB is completely inactive on Night 1, as he does not become active until Night 2. He starts in the Game Area and will eventually come to the Office via the Left Air Vent. With each of his movements, the player can hear him saying "Hello," "Hi," or simply giggling. BB will not show up on any cameras except the Game Area and the Left Air Vent, keeping his path of approach hidden.

Balloon Boy (other than some of the easter eggs like Shadow Freddy) is the only animatronic in the game that will not kill the night guard, but rather he will make an annoyance of himself by disabling the Flashlight and Air Vent Lights all while a sound loop of him laughing will play until the player is killed or gets to 6am. If this occurs, the player is especially vulnerable to Withered Foxy's attack, as he can no longer be stunned with the now disabled Flashlight. To prevent Balloon Boy from fully entering the office, the player must put the Freddy Fazbear Head on while BB is in the Left Air Vent, and wait for the sound cue that he has exited the vent. However, the player should be advised that the noise heard may possible be another animatronic entering or exiting the Office or vents. Once BB has left the vent, he will return to the Game Area, and his cycle will repeat. If the player instead pulls up the monitor while BB is still in the vent, he will enter the Office. Balloon Boy will remain in the Office for the rest of the night, rendering it nearly impossible to beat unless it is close enough to 6 AM or Foxy's AI is set to 0 on the Custom Night.

From the Custom Night, night modes where BB is active are listed as follows: While Balloon Boy himself does not appear in Five Nights at Freddy's 3, Phantom BB is one of the antagonists in that game. However, Phantom BB is only a hallucination and not BB himself.
 * New & Shiny
 * Night of Misfits
 * Freddy's Circus
 * Cupcake Challenge
 * Fazbear Fever
 * Golden Freddy

The real BB's disembodied, deactivated head appears in the trash can along with the remains of the other toy animatronics. The head's appearance does not affect gameplay and is only there for aesthetic purposes.

The audio system players use to ward away Springtrap is actually BB's voice box, which is the biggest role BB plays besides his head and mini game appearance. Drawings of BB can also be seen on CAM 03 and CAM 08.

BB's most important appearance is in the minigame "BB's Air Adventure". The player can access this minigame at any time on any night, by going to CAM 08 and double-clicking the drawing of BB on the wall.

In this minigame, the player (playing as BB) must collect eight red balloons scattered throughout a map. Seven can be collected by simply walking to the right, and upon doing this, an exit door will appear. Touching said door will end the minigame, or the player can continue the minigame, as instructed below.

Once the first seven balloons are collected, the player can jump out of an invisible exit at the top left corner of the room. Once the player does this, they will fall to a black-and-white area, until they hit the ground, in which case they can proceed to the right to discover another "room" with a color-changing balloon. The player must touch this balloon to end the minigame.

Once the player acquires the birthday cake from the minigame Mangle's Quest on Night 2, they must return to BB's Air Adventure. They must collect the seven balloons again, jump through the invisible hole again, land on the red balloon platforms, and walk over to a seemingly-deceased child. Approaching the child will cause a large cake to appear. The child will stop crying, look up at BB, and the minigame will abruptly end. This unlocks one of the children in the Happiest Day minigame.

Although Balloon Boy doesn't make any appearances at all in Five Nights at Freddy's 4, his nightmarish counterpart, Nightmare Balloon Boy, does play a significant role for the Halloween Edition in the "Fun with Balloon Boy" minigame. It is noted that BB's all lines are reused for Nightmare Balloon Boy, only low-pitched.

BB in his FNaF World self appears in few minigames such as "Gravity Vortex", "Lemonade Clown" and "Fruit Punch Clown".