Apache silent kill technique & camouflage level; The highest caliber still used by Special Forces troops, and Marines in the military today.

(Translation in regard to Q's post; Bye, bye sleeper cell's)

More info:

Apaches have the highest level knife skill and camouflage techniques. They were known as the invisible people. The colonizers were unable to defeat this tribe. Their techniques adopted and used by special forces and marines for training.

The Apache women would fight as fierce as the men. One of their techniques was to slit the throat so that their victim would be silent.

Colonising troops would send in whole regimens on horseback, thousands at a time, into apache camps. There they would find only elderly people and children. The Apache men would be gone raiding the troops camp. The women would be left behind in hiding to catch the troops off guard and slit their throats and kill every last one of them. Then they would send every horse back without riders (thousands). And completely demoralize the enemy. The Apache were the only tribe that was never defeated.