The Defensive Arsenal: No Doors, No Mercy
In FNaF 2, Scott Cawthon replaced the limited power/door mechanic with a more complex set of tools. Success depends on how fast you can switch between them. fnaf 2

The Freddy Fazbear Mask: Your primary shield. By donning the mask, you trick the animatronics (except for Foxy and The Puppet) into thinking you are one of them.
The Tactical Flashlight: Crucial for spotting animatronics in the pitch-black hallway and side vents. More importantly, it is the only way to stun Withered Foxy and keep him from pouncing.
The Music Box (Cam 11): This is the games "stress engine." You must constantly wind the box remotely. If the song ends, The Puppet emerges, and no mask or light can save you.