Henteko is a beautiful city created by Asmodean.
The town is not shown on the current map but is due west of Stensele.
It's the home of the Ninja's Guild. Located through the northeast passage of the main town area.
In the center is the palace where you'll start the infamous Henteko Quest. Once completed you'll have access to diamond weapon smithing which is located southeast of town in the tabbacco farms.
You'll also find a nice RD north and then east a couple maps from the Ninja's Guild.