Orgianlna version of mod is by LUNG
Https://moddingofisaac.com/mod/413/heretic-mod

Unfortunately, there are a lot of bugs, because the version of afterbirth has been changed to afterbrith plus, is that correct? - no, I do not have time for such classes now working on the more modification :v

*A new set of Characters
*A floor overhaul!
*New music!
*Over 1700+ new rooms!
*Lots of new monsters and bosses!
*20 new challenges!
*Various minor improvements!
*More crawlspace quests!
*Custom Items!
*Updated pools!
*And much more!
*New bosses
*More combo boss rooms!
*Challenges