A developer who has kept secrets hidden from players for over 20 years.

Doom 2 co-developer John Romero left a congratulatory message to the user who revealed the secret and informed him of the conditions for unlocking the secret.

The method is that the player must never enter the area where the teleporter is located.

Instead, the secret only worked if you entered while being pushed away by the monster.

It took 24 years after the game was released for this secret to be revealed.