Blackbeard was profoundly thirsty for the Yami Yami no Mi (Dark Dark fruit) for years, and he, as far as we know, had no interest in any other devil fruit during this time.

– The Yami Yami no Mi allows its user to suppress/nullify other devil fruit functions.

– Blackbeard does not sleep

[As far as I know] every popular theory about how Blackbeard can consume multiple fruits and live says that it’s his body that facilitates this, meaning he lived his whole life with the ability to eat more than one devil fruit and still was only after one.

I’ve also heard that Oda’s editor stated that nobody has accurately theorized how Blackbeard can eat multiple fruits, so, assuming this is true, the multi-heart theory gets thrown out the window because it’s widespread enough for him to undoubtedly have seen it.

It seems rather clear that the Yami Yami no Mi has allowed Blackbeard to eat multiple fruits, because otherwise he had no reason to only want that one fruit and no reason to not eat another devil fruit before the Dark Dark fruit.

With that in mind, maybe the Yami Yami no Mi has allowed Blackbeard to suppress the aspect of devil fruits that kill you if you eat more than one. Why has this never been done? Because it’s an active thing.

He is constantly using his fruit to prevent his other fruit(s) from killing him, and if he ever stops, he dies. Meaning that if anybody other than Blackbeard ever did this, they would be dead very soon because the moment they go to sleep they could no longer use the fruit to keep themselves alive.

But since Blackbeard doesn’t sleep, this isn’t a concern. We even got confirmation in film red that there isn’t a non-life threatening way to prevent yourself from sleeping, so that bolsters the theory as well because it shows there isn’t a way to avoid the no-sleep thing, but Blackbeard doesn’t have to. Thoughts?

Theory by LEMO2000 (