Arimaa/Lone Elephant Attacks
A Lone Elephant Attack occurs when the elephant advances while the rest of the army stays behind. Extended lone elephant attacks are now rare, but may work if the opponent doesn't move the game in a different direction.
Reasons to use the Lone Elephant Attack
By pulling rabbits, the gold elephant has disrupted northeast trap defenses. (Game)
- to push and pull enemy pieces toward one's home traps for potential capture
- to disrupt the enemy defensive position
- to threaten capture in a poorly defended away trap, perhaps during a race
At right, the gold elephant has pulled two silver rabbits to the sixth rank and seriously disturbed Silver's northeastern trap defense. A crucial defensive square, g6, is now occupied by the weakest silver defender, which cannot move until f6, h6, or g5 is empty. Gold might soon pull a rabbit further south for eventual capture in f3, or might try to drive away the silver camel so that the gold horse could safely advance and perhaps occupy g6. If Gold pulls a rabbit further down, Silver might consider swarming the southeast trap.
Risks Involved with the Lone Elephant Attack
- Advancing an elephant beyond the 6th rank, or into a corner, may expose it to a blockade.
- If the elephant wanders too far from its home traps, they may become increasingly vulnerable to a multi-piece attack.
- Enemy rabbits dragged homeward, but not captured, may later become goal threats.
- One who keeps nearly all friendly pieces at home could become cramped if the opponent plays aggressively.
Defense and Counter-Attacks
When the enemy elephant pulls non-rabbit pieces, there are defensive and counter-attacking options:
- use friendly pieces, especially the elephant, to help pulled pieces retreat
- respond in kind, pulling enemy pieces homeward
- launch a multi-piece attack, which might make it hard for the opponent to continue with lone elephant play
When the opponent pulls rabbits, the options are similar, but narrower. Since rabbits can't retreat homeward, it is urgent to counterattack somehow.
Dual Lone Elephant games
Dual Lone Elephant game after 9s.
A Dual Lone Elephant game occurs when both players employ a Lone Elephant Attack. This Dual Lone Elephant game featured attempts by both players to drag pieces homeward for potential capture. Such a game can be quite slow, since an elephant can often guide a threatened piece to safety. A Dual Lone Elephant opening can go on and on without capture, until eventually one player makes a critical mistake or switches gears. In this case, however, there was a way to move things along even with lone elephant play; the d- and e-file rabbits were vulnerable. Since a rabbit can only step sideways or forward, a rabbit pull in the center will disrupt a home-oriented game.
Unlike Gold, Silver has placed all eight rabbits on her home rank. From here, Silver should not attempt a Lone Elephant Attack, as her own d8 and e8 rabbits are vulnerable.
To prevent central rabbit pulls, Arimaa players often use a 99of9 setup and move a rabbit to the d- or e-file only when a central goal must be blocked. Any other piece pulled in the center can retreat, and a rabbit pull on a flank would be riskier and less beneficial for the opponent. One who intends to begin with a Lone Elephant Attack should leave his own rabbits off the d- and e-files initially, so as not to fall behind in a potential Dual Lone Elephant game.
In a Dual Lone Elephant game, both players may be content to pull pieces on opposite wings and engage in a slow but steady war of attrition. Goal defenses will gradually weaken, and one side or the other will eventually win. Rather than simply play this out, one might transition to a multi-piece attack.
In this Dual Lone Elephant game, each side tried to disrupt the other's defensive position with sweeps beneath the traps, rabbit pulls along the perimeter, and threats to push stronger pieces into the center. Gold's patient and precise technique won out, as he was up by four rabbits before any other piece was captured. Had Silver played differently, however, Gold would not have had time for this kind of play.