All's fair in love and war
Scorched Earth Politics
The Russians and their use of a scorched Earth policy. I can’t think of a better way to flip off your invaders than ruining all your own shit so when they do take it, it’s worthless. Not only that, but the land itself is just too damn cold. So go ahead, take the land. You will just freeze to death. Congratulations. (MonkeyXing)
Into the Cannons
Not so dirty, but Turks had the Turan tactic.
The army would formate into a crescent, with the arms of the crescent being the armored, strong divisions and middle front being the fastest divisions and middle back being the highest firepower(cannons). They’d start the battle lined up and charge, then the fast middle front guys would start retreating to the lines behind the middle back(the cannons). The arms of the crescent would hold firm because they were the armored part. The enemy would think they were retreating completely(because it looks like they are losing their s**t and also their formation)and would chase after them only to be met with the cannons and to be encircled by the crescent’s arms. It was a slaughter of the enemy after that. (ArefArif9)
Back in the English Civil War there was a certain nobility in battle where you were supposed to be able to see your opponents and you would stand and fight, Cromwell decided this was stupid and in numerous battles would send troops round the side hidden by trees and bushes to tear through the Cavaliers before the fight properly began. Was a lot dirtier a trick at the time (Nooksybayor)