I know Halo of Flies counts, but does Pretty Fly (pill or slot machine) count towards the transformation?
Does Pretty Fly count towards Lord of the Flies transformation
the-binding-of-isaac-rebirth
Related Solutions
Those symbols tell you, which "end boss" you have defeated with the current character.
With your Isaac, you defeated Mom's heart (heart), Satan in Sheol (upside down cross) and Isaac in the Cathedral (cross).
The red tint tells you, that you defeated them during hard mode.
In the spoiler, you'll see the rest of the symbols
1. Mom's heart | 2. Isaac | 3. Boss rush | 4. Satan | 5. ??? / Blue baby | 6. The Lamb
I've asked the same question on the SteamCommunity Forum, and this is the outcome:
Nope, they don't sadly.
I know because I've tried it, was getting nothing but Breakfast which meant I had exhausted the entire pool. But none of the items that I needed to find were in the collection page.
EDIT:
There are different opinions, so it's a bit confusing, another guy posted this answer:
I haven't unlocked these yet and somehow they're there.
Meaning that he hasn't unlocked The Lost items (The Soul, The Body and The Mind) but they are shown in his collection page. So it appears to be true.
Best Answer
No, the pretty fly through pill or slot machine does not count towards the transformation.
In some runs, I've got more than 3 pretty fly pills, but 1) I did not transform and 2) I still had to get 3 items required to transform.
Only the items listed here will transform you into lord of the flies.