(Question) Why didn't Killer Bee help fight against Obito and Madra alongside Naruto and co.

Did I miss something, or was there a reason Killer Bee wasn't fighting? I get that the power levels had gone insane by then, but he's a powerful jinchuriki with the only other Tailed Beast left besides Naruto and Minato. What's the deal there? Where was he when Obito and Madara went Six Paths Mode?