the crucifix

[Un pigeon étonné]

I unlock the crucifix but i don't have it in my succes and idk what does this item?

[Justice]

I think you're talking about The relic (blue cross)

https://bindingofisaac.fandom.com/wiki/The_Relic

[Un pigeon étonné]

nope i already have the relic

[Justice]

https://vignette.wikia.nocookie.net/bindingofisaac/images/5/57/Celtic_Cross_Icon.png/revision/latest?cb=20140221164214&path-prefix=es
Celtic cross then?
Ocassionaly activates invincibility shield upong taking damage

[Un pigeon étonné]

nope xD i found nothing on this secret but i think i unlock it when i bit the final chapter without taking damage

[No-Heart]

take a look at this site, it has all the items
https://platinumgod.co.uk/original