Episode 3
After acquiring the Azoth Sword, Miki is ambushed by Marcus and Miura. Amon forges a prosthetic arm out of the sword Shiryu to replace Gai's lost limb.
Aired 23/03/2018EP 3 - Episode 3
2018
SWORDGAI The Animation
The story revolves around Gai, who was born beside a woman who met her death in a forest. He was adopted by the swordsmith Amon. A few years later, Gai becomes Amon's apprentice, and during the forging of a sword, he loses his right arm. To help him, Amon crushes the demon sword Shiryuu (lit. Death Dragon) to form it into Gai's replacement right arm. Gai then is able to fuse with the weapon on his arm, and fights against his enemies.
(Source: Anime News Network)