One characteristic could be the use of underhanded tactics. For example, in some true stories, there might be instances of false flag operations. This is where one side pretends to be from another group to create confusion or mislead the enemy.
It could be about various things. Maybe it's about unconventional combat tactics that were used in a real - life conflict. For example, it might involve guerrilla warfare, where the rules of traditional 'gentlemanly' warfare are not followed. This could include things like surprise attacks, using the environment in unorthodox ways, or targeting non - military infrastructure in a strategic sense.