Honkai: Star Rail - A Flash

Sinopsis Film

A fleeting flash — thus is the speed of swift blades as the master and her student spar, and thus is the passage of the unceasing torrent of time. Just how long has it been? His duel with his master, centuries ago, still rippled like a memory from yesterday. But the few years between now and when he took in the boy as his student felt like a lifetime. Time gallops, swift as a stallion, sudden as a lightning strike, agonizing as a blade that runs him through. And yet, it feels like everything has always been the same.