Ultimate Custom Night is the ultimate mashup of the Five Nights at Freddy's franchise, where you'll once again be trapped alone in an office, fending off a diverse cast of 50 selectable killer animatronics from across seven games. The options for customization are nearly endless, as you can mix and match any assortment of characters and set their difficulty from 0 to 20, then jump right into the action. From your office desk, you'll need to manage two side doors, two vents, and two air hoses, all of which lead directly into your office. To complete the ultimate challenges, you'll also have to master other tools, such as the heater, A/C, a global music box, a power generator, and more. Additionally, you'll need to set up laser traps in the vents, collect Faz-Coins, and purchase items from the Prize Counter, all while keeping a close eye on two Pirate Cove curtains. The game also features a challenge menu with 16 themed challenges, voice acting from returning favorites as well as new arrivals to the franchise, and unlockable office skins and cutscenes. The interface and audio are in English, with subtitles available in French, German, Dutch, Spanish (Latin America), Italian, Portuguese (Brazil), Russian, Japanese, Chinese (Simplified), and Korean.