What happens in the 3rd victory lap if I don't have The Lost?

According to the wiki if you start your 3rd victory lap your character will automatically turn into The Lost.

I haven't unlocked the character yet and I was wondering what will happen if I start my 3rd lap. Will I turn into The Lost and maybe even unlock him? Or will I just keep playing as my current character?

3 Answers

According to the wiki you linked:

Achievements cannot be unlocked during a victory lap

then no, you can't unlock The Lost in that way.

But I don't see why you won't be turned into The Lost even if you haven't unlocked it yet. It's a fixed character, like a daily run or a challenge.

2

You are indeed automatically turning into The Lost, and this is permanent for the next victory laps of the same run. This person on Reddit also talked about it and some other details about going down with the victory laps:

At the start of your 3rd lap (so your 4th time on Basement) you are transformed into the Lost. As far as I know, this is permanent. Lost has the same recent items as your previous lap, you don't automatically get Holy Mantle, one hit you're done.

But it doesn't seem like you are unlocking The Lost as a playable character by becoming him with this lap. It seems than the only way to unlock The Lost in Afterbirth is to hold a Missing Poster and to die in a Sacrifice Room.

1

I played through it without having unlocked The Lost first, and I turned into The Lost. Due to that bug that lets you unlock achievements in victory laps, I unlocked an item. The Lost has not been unlocked from doing so.