The Flashlight is one of the most important tools in your arsenal as you find a way to escape the pizzaplex. That is why it is important that you upgrade it whenever possible. Hidden deep within the pizzaplex is an upgrade for the Flashlight’s battery. Here is where you can find the Flashlight Battery Upgrade in Five Nights at Freddy’s: Security Breach.
When you reach the part of the game where you escape from Vanny for the first time, you will be tasked to meet Freddy at Roxy Raceway. After meeting Freddy, you are told that you will need to go through the backstage and find the rehearsal room. The rehearsal room is found at the end of a long hallway backstage. It is here that you will find the upgrade you seek.
Be careful of Roxanne when you are heading to the rehearsal room. She is relentless. Keep watch for the security bots when maneuvering through the hallway as well. When you enter the rehearsal room, there will be a room on your left. Head in there and check around for a green gift box. Open up the gift box to get the Flashlight Battery Upgrade.
