Kidou Senshi Gundam: Cucuruz Doan no Shima

After a covert mission goes wrong, Mobile Suit pilot Amuro Ray and his comrades are stranded on a remote island. The battalion was sent to a land called the Island of No Return to clear off any enemy forces, only to find a group of children and an enemy mecha attack. Now Amuro must find a way for them all to escape this mysterious land, but not before meeting a strange man—Cucuruz Doan.

(Source: Crunchyroll)