So, i just wanted to say how i ended up beating 4/20 mode, since so many people seem to be struggling, or even hating the games difficulty.
So, overall, I start the night by setting the camera to Pirate's Cove, then bringing up the camera every second and pulling it down immediately. If the camera gets disabled, I don't use it at all for about 4 seconds. If Bonnie or Chica are at the door, look at the main room cam to see them leave. If i see them, or see the camera be disabled, I open the door and never, EVER, use the lights. Freddy and Foxy move just about whenever the fuck they want, but won't move if the camera is up. When Foxy leaves the cove, i wait 5 seconds, then look at the hallway and wait for the last possible second to close the door, waiting a second longer for her to leave. With the way I have it, Freddy only makes it to my door midway through 3 am and I have 55% power left, assuming foxy attacks once. I never use the camera to find Freddy, just remember where she is based on her number of laughs. When she gets to the door, I count 3 seconds and close the door until she leaves. While Freddy is at the door, I don't use the camera unless Chica is also at the door. Mind you, there is a fair amount of rng, with Foxy's runs and Freddy camping the door, though I have been able to consistently beat the night with 10% power left using this "strategy".