Kabaneri of the Iron Fortress (2016)

S1E4 Flowing Blood

The rest of the group secures Ikoma and Mumei inside the back compartment, leaving the Kotetsujyo without two of its most formidable warriors. Suddenly, they find themselves under siege as Kabane swarm the train. To make matters worse, one of the attackers is a Wazatori, a unique Kabane capable of adapting and growing more powerful with every encounter...