He had part of his tailed ripped off in the battle previous and just used thatt.
The 8-tails left a piece of his Tentacle left behind which contained enough chakra for Bee to survive off after being extracted from him. Can't remember if he lost it in the war or if he cut it off before he was fully extracted though.
Oh so he used that one
He chopped off the tentacle himself on-panel as he was being dragged into the Mazou.
Anyone??
When he was extracted by the Gedou Mazou by alive Madara
We can assume that Bee used to keep his seal over the Hachibi weak cause they were Friends. In that battle, the Hachibi took control of Bee voluntarily (Like Kuruma does with Naruto) and put some of his chakra in Bee and expelled him. Since Bee was expelled by the Hachibi and the seal broke, Hachibi was not ripped out by the Gedo Mazou from Bee.
Since Hachibi was not forcibly extracted from Bee, Bee survived.![]()