The Koa e Ko'ia is a spacecraft race that combines marathon flights with physical endurance. Held every Xi'an year (MXY) in alternating locations around the Xi'an Empire, it was first competed in MXY III.690 (SEY 2341) in the Hyoton system. Before each race, the Koa e Ko'ia governing body chooses checkpoints and destinations that are not revealed until the race begins. There is always a mixture of locations in space and in atmosphere.
Once the race is underway, pilots receive the coordinates of their first checkpoint, and do not learn their second checkpoint until reaching the first, or their third checkpoint until they reach the second, and so on. Pilots must coordinate with their pit crews about when and where they will rest, repair, and refuel, and must choose strategic periods in which to lower their metabolism and extend their flying time without reaching a state of exhaustion. This continues until only one racer is left, which can vary anywhere between 200 and 50 Standard Earth Hours. The pilot who has reached the most checkpoints is declared the winner. Non-Xi'an people were allowed to participate for the first time in SEY 2947.