Godzilla X Gundam: Monster Era

In 1954, mankind was reminded of its place among nature the very day the first Kaiju, Godzilla, came ashore and tore Tokyo asunder. As the years went on, more and more of the Kaiju began to appear, until 2020 when they disappeared. However, humanity (along with an ancient civilization) has not taken the time to dawdle and have constructed powerful mobile suits called Gundams to stand equal to monsters that might as well be gods should they ever return. Among this is a young woman of half-blood descent preparing for a war some say will never come again... or so they think.