why challenge №4 not unlock?

[Heartbeat]

i'm complete cathedral damn 5 times and it's challenge not unlock

[Nazemec]

You have to beat the Cathedral as Eve specifically.

Also:
List of things that prevent all kind of progress:
- Seeds (except a few special ones)
- Challenges (except for their reward obviously).
- Daily Runs.
- Reruns and Victory Laps (except for a few specific unlocks).
- (AB+) Any active mod from the mod menu before Mom is killed once on that save (no matter what they do, other saves are irrelevant).
- (Rep) Enabling the debug console in the config files.
- Paranoid antivirus programs (or missing rights) preventing the game from creating/editing its save file.

[blunus]

Darkness Falls contains Razor Blade and Sacrificial Dagger, in which you have to defeat Satan and ??? as Eve to unlock.

Beating Isaac unlocks Eve's Bird Foot, not the dagger.

[Nazemec]

Originally posted by blunus:

Darkness Falls contains Razor Blade and Sacrificial Dagger, in which you have to defeat Satan and ??? as Eve to unlock.

Beating Isaac unlocks Eve's Bird Foot, not the dagger.

Checked the wiki more carefully. Interesting how it has contradicting informations.

On one hand, it mentions "defeat Isaac as Eve". On the other, in the same page, it mentions you have to unlock It Lives (kill heart 11 times), Eve (duh), and the Sacrifical Dagger (killing ??? as Eve).
https://bindingofisaacrebirth.fandom.com/wiki/Darkness_Falls