So, the secret character was going to have a random mechanic, it would have 4 to choose from, here they are.

Mechanic 1: Silly Shenanigans (i lost the original name)

Basically, it would distract you with ads, fake jumpscares and even cover the cameras!

(non-lethal)

Mechanic 2: Minigames

Randomly, a minigame would appear on the screen. It had 3 to choose from: Find the coins, Hide & Seek and Bomb Tag (you just had to give the bomb to it before time ran out)
(Lethal)

Mechanic 3: Impersonation

It would impersonate one of the characters in the game already and make it harder

(lethal)

Mechanic 4: Normal
You had to electrocute it before it started running to your office, which at that point, it'd be too late. For those wondering, yes, there would be limited uses.
(lethal)

I had 2 out of 4 mechanics done before changing the base mechanic once in for all; Minigames and Normal. I started working with the Silly Shenanigans mechanic 2 days prior before changing the base mechanic.