Japan might be an island, but that doesn't mean they're completely isolated from foreign hostility. This episode features the tale of how Hojo Tokimune managed to fend off Kublai Khan's attempts to reach Japan.
Yes. Just as it was written 
in the Black Yuan Scrolls.
Sï. Lo decían los Pergaminos
Negros de Yuan.
Vão, assim como escrito nos
pergaminhos pretos de Yuan.