Antibirth, the free fan made Binding of Isaac: Rebirth expansion, is available for all PC players. Antibirth is not to be confused with The Binding of Isaac: Afterbirth, which is an official piece of DLC. This is a free, fan made expansion, and not an official one.
If you have The Binding of Isaac: Rebirth and are still hungry for more content, be sure to check the Antibirth Page. You can download the free expansion/ mod from there.
Some of the elements included in this mod are:
- 2 new characters with unique playstyles
- 90+ new collectible items to help Isaac fight
- 18+ new trinkets to swap and strategize with
- 80+ new enemies to face one after another
- 16+ new bosses to kill or be killed by
- 4000+ new rooms to explore and survive
- A new secret final chapter for Isaac to endure
- Bigger and greater secrets than ever before
- Several new or enhanced features for local cooperative play
- A nearly full and original new soundtrack, evocative of classic Isaac
Antibirth is a mod, so there are some technical constraints. It doesn’t work on consoles and it is not compatible with the Linux/OSX versions. It is not compatible with Afterbirth or Afterbirth +, as it is a Rebirth-only mod. You can’t have both Afterbirth and Antibirth active, but you can easily switch between the two at any time.
One of the best things about Antibirth are the cooperative play changes. If you like this mod, you can support the creators in several ways, all explained on their web page.
Cooperative spelunkers using the same computer can now control two complete, independent characters with their own separate items, actives, upgrades, trinkets, and consumables! Isaac and a friend can now embark on the full treacherous experience at once and even unlock things in half the time, or maybe twice the time if they’re not so great at teamwork, but at least they’re free to test the limits of their friendship while the monsters test their mettle.