Little Ronin by Loyd Elmore Jr HB

Before the lab fire, before the lab experiments escaped
to the land beyond the stream, and before Malinville
was formed, a few were sent to a new lab where they
became what they were designed to be - assassins.
Trained by a man who knew the ways of the samurai,
they became what they were intended to be.
But like those who would escaped the lab they came from,
the samurai would soon decide they needed to escape.
When their master was taken, and they faced a
long trip back to seek revenge, the 6-inch samurai would become…Little Ronin.