Brave Bang Bravern!

Bang Brave Bang Bravern is set in a world where humanoid armored weapons known as “Titatonostrider” (“TS” for short) are used in warfare. The story kicks off when troops from various countries converge on the island of Oahu, Hawaii, including the main characters, Ao Isami of the Japan Ground Self-Defense Force and Lewis Smith of the United States Marine Corps. Isami and Smith cross paths during battle, but suddenly their teams are attacked by an unknown enemy, scattering soldiers and sending their forces into disarray. In order to save their friends and survive on the deadly battlefield, they must fight with every ounce of courage and pride that they can muster.

(Source: Crunchyroll News)