The Mandela Effect is a naturally occurring phenomenon that is a result of time travelers changing the history of any given world line. Basically, whenever a time traveler causes a world line split, think of one offshoot as a dominant line and the other as recessive. The Mandela Effect happens whenever you remember some history from the recessive world line. For example, I don’t know if any of you have noticed, but the flag of the USSR just changed. That holo star wasn’t there before.