While playing The Binding of Isaac: Afterbirth, I noticed that I got a huge amount of black hearts, which never happened to me before. I already know a lot of items, but it looks like some of them synergized with each other... Here's what I had at the end of the game, along with my game seed:
Which item(s) could cause that?
The only item there which causes black heart generation is The Virus, but that only gives you black hearts if you touch enemies and they die from the poison damage. You also have Taurus, which grants invincibility and contact damage after being in a room long enough. It's possible that killing enemies with the Taurus damage is counting as killing them with The Virus, or that you were damaging them with Taurus and then the poison took over. I'm not sure how that synergy works.
It's also possible you just had a lot of black heart drops. There are certain room layouts that can lead to this pretty easily, like a Devil Room that just has 3 black hearts sitting on the floor. In my experience it's not that uncommon to get this number of hearts if you aren't getting hit a lot.
If the last item of the second row is Gimpy, then it could be another source of your Black Hearts.
Whenever Isaac takes damage, there is a chance that a Soul Heart or a Black Heart might spawn.
