Stratego Mobility and Protection
The first phase of any game of Stratego, the opening, generally sees basic exchanges of Lieutenants and Sergeants in the center of the board. Perhaps a Captain or another major piece will be uncovered, but—between strong players, at least—that is usually about all that happens.
What, then, are the next goals of the players? Usually, during the next phase of the game (the middlegame), the players attempt to increase the mobility of their forces and to create tension on both flanks, and perhaps also in the center.
Mobility refers to the ability of pieces in one’s army to travel freely from one flank to another.
Usually, Red and Blue strive in the middlegame to increase their mobility along the fourth rank and the seventh rank, respectively. A clear fourth rank allows Red to transfer his major pieces quickly from one part of the board to the other:
Red has mobility along his fourth rank, allowing him to swing his major pieces into battle freely at any moment. Red’s Two Mill (along the e-file) also enjoys high mobility. Red is able to swiftly transfer his Scouts to any part of the board in order to gain information in a timely fashion.
Protection refers to a player’s ability to guard against probing techniques on the flanks or in the Center. Here, Red has taken pains in his initial setup to make his position difficult to attack.
His Right Flank is well-protected against incursion, since an advance by Blue’s Marshall on that side—say, into the i4 square—could be met by General h3-h4 and Spy g3-h3, cutting the Marshall off from the Center.
Blue would then need to penetrate the Right Flank with a Miner (moving it to the j4 square, and then dismantling the bomb on j3), but even then he would lose the Miner swiftly in the process. Even if the assault on the Right Flank were successful, Blue could hope to win the pieces on h2, i2, j2, i1, and j1—not a big haul for so much effort.
Red’s Left Flank, on the other hand, is also well-protected. If Blue sends his Marshall against that side, Red will be able to trade it off swiftly by swinging his own Marshall from d3 out to d4, then to c4 or b4. After the trade, Red’s General could then swing out quickly from the Right Flank back to the Left Flank (if that is where it is needed), or could be sent into enemy lines in any other part of the board for a probing attack, supporting by Red’s highly mobile Scout Mill.
Finally, in the Center, Red has also taken care to protect himself, since either his General or his Marshall can swing there quickly. The Scout on g3 also helps defend the Red Captain on f3 from a direct assault by blue’s Marshall.
Additionally, Red’s Scout Mill will make it easy to identify the identity of any incoming attacker, and so Red will be able to send the appropriate troops to halt the Blue offense.
Thus, mobility and protection are related concepts.
A mobile army will be able to defend itself from possible attacks. Mobility is most frequently hindered by clutter along the fourth rank and poor bomb placements.
Contrast the above position, designed by an advanced Stratego player, with the following one, played by an amateur:
To get part two Stratego Mobility and Protection (Part 2).