Strategy for Black: Barricades and Cordons 1
Black’s first concern, at least during the early stages of the game, is to gain control of the corners. Indeed, it is perfectly possible, and advisable, to block off the corners altogether. Look at these defensive positions – called barricades.
There is no way that a white warrior or the king can get past these lines of black warriors.
Because neither warriors nor king can move diagonally, or jump over other warriors, white must consider this corner well and truly blocked, at least until one of the black ones moves away.
This is the simplest form of the barricade, but there are many others.