It also allows players to train intelligence cells and conduct covert warfare.

You've confirmed that you don't believe Accord is behind this covert ecological warfare.

The story revolves around a traditional Ninja warrior who must adapt to operate in the modern world of covert warfare.

Why aren't we using that term instead of the mealy mouthed "covert warfare"?

Trainees had to go through a variety of situations to get them used to what covert warfare was like.

The first specialized training began in the mid-15th century, when certain samurai families started to focus on covert warfare, including espionage and assassination.

AIs have also begun engaging in covert warfare against each other.

Lord Merkeset would be the next in line as regent, but there will be covert warfare amongst all the nobility for the position.

Unit 731, covert biological warfare human experimentation unit of the Japanese Army (1937-1945)

The U.S. is fighting covert and overt warfare in 18 different nations at this time.