You will know “The cake is a lie” like halfway into the game, when you first find the open wall panels and look in the little hidey-hole. You don’t even have to come close to beating it.
The real trick to knowing someone beat it is when they recognize that the cake isn’t a lie, because the credits show you the cake. You’re never promised cake, you’re just told that there is cake and the credits show it to you. Ratman never made it far enough to see the cake, which is why he thinks it’s a lie
You will know “The cake is a lie” like halfway into the game, when you first find the open wall panels and look in the little hidey-hole. You don’t even have to come close to beating it.
The real trick to knowing someone beat it is when they recognize that the cake isn’t a lie, because the credits show you the cake. You’re never promised cake, you’re just told that there is cake and the credits show it to you. Ratman never made it far enough to see the cake, which is why he thinks it’s a lie