okay, I know one:

Kunoichi Turtle (because there is only one female boss plus this one):
Uses two sais to scratch, dmg 1. When you hit her first time she throws sais to you and draws her sword. Sword dmg 1. She swings like mad within sword and then she often throws several SHAKENS; stars to you. when her energy is at smallest one, she starts throwing smoke bombs and if they hit you, you can't move, and then she continues throwing shakens. When she is only one hit left before die, she throws her sword, picks up second from her back, and then she jumps around and if you shoot she deflects every bullet, then she block few bullets so they fly back to you and then you paralyze to second, when she takes Kusari-Gama and starts messing around, and you must get flamethrower ammo those starts to drop sometime and burn her up. Then she draws knife and does harakiri, and then ninja jumps around, but he just swings sword and you must just shoot him, few times are enough.

Inu-Maru (aka Dog-Maru)
Inu-Maru is little cute dog, but if you walk closer it bites you. dmg 2. if you shoot it before the bullet is at target it barks and ninja jumps to deflect bullet (s). Then you can try what ninja guards do when you try else guns. Then, just if you wait too long kunoichi comes and takes it away.