Aldnoah.Zero

A hypergate discovered on the Moon once opened the way to Mars, where settlers uncovered an ancient technology of overwhelming power known as Aldnoah. They eventually formed the Vers Empire and grew so distant from Earth that rivalry became war, until the destruction of the lunar gate caused the catastrophe called Heaven's Fall and forced both sides into an uneasy fifteen-year ceasefire.

The peace collapses when Princess Asseylum visits Earth hoping to improve relations and becomes the target of a staged assassination used to justify a full Martian invasion. Student Inaho Kaizuka and his friends suddenly face war machines whose abilities appear impossible to overcome. Against overwhelming technology, Inaho relies on his composure and relentless analysis to find the weaknesses that may keep Earth from being crushed.