Ok so we have the scabbards that are chilling and laughing just after ashura sacrificed his life for their stupidity and he is probaly dead.
Yamato who spent all his time with the only goal of protecting momo has now out of nowhere decided to leave him alone and go to fight. Shallow writing chapter again.
Oh and Nami speedblitz an emperor in hitting Ulti, all good here.
It is samurai mentality. Death is a part of their duty, their expectation in fulfilling their service, and to complain about pain in that regard is unfitting. It's why Kiku can joke about losing an arm, why they completely deny hunger, etc
Yamato knows that Momonosuke at this point is secure.
And Nami merely took the initiative, but since she attacks with lightning yeah, she's pretty fast actually.