Arimaa/Race Positions

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8 Arimaa rs.svg Arimaa rs.svg Arimaa rs.svg Arimaa cs.svg Arimaa cs.svg Arimaa rs.svg Arimaa rs.svg Arimaa rs.svg 8
7 Arimaa ds.svg Arimaa hs.svg Arimaa eg.svg Arimaa ms.svg Arimaa rs.svg 7
6 Arimaa rs.svg 6
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3 Arimaa hs.svg Arimaa es.svg Arimaa dg.svg 3
2 Arimaa rg.svg Arimaa dg.svg Arimaa hg.svg Arimaa cg.svg Arimaa cg.svg Arimaa mg.svg Arimaa hg.svg Arimaa rg.svg 2
1 Arimaa rg.svg Arimaa rg.svg Arimaa rg.svg Arimaa rg.svg Arimaa rg.svg Arimaa rg.svg 1
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This is currently a capture race, but the ultimate question is who can reach goal first.

A race position occurs when both sides can make quick progress in different parts of the board. A race will slow or stop when one side chooses defense over offense. If both sides keep racing, the race will end with a forced goal; if the opponent is better positioned for this, one must turn to defense before it is too late.

In the position at right, from this game, each side left a home trap vulnerable. Opting to race, Gold has just captured a silver dog; Silver can capture the c2 horse, but then Gold could capture the silver camel. Even after this capture, however, the gold elephant would be relatively isolated, which is costly in a race. Gold's first mistake was in the initial setup; the situation here shows why a horse is usually not placed on the c- or f-file. Had the gold horse started on b2, it could have stepped to b3, giving Gold control of the c3 trap. Instead, Silver quickly achieved a common first objective of a trap attack: getting one's own horse onto a decentralized key square of an away trap. From here, the silver elephant captured the c2 horse in three steps, leaving a fourth step for the e8 cat to advance to e7, which forced the gold elephant to end the camel capture on g6, from where it couldn't immediately make another capture, which let Silver catch up. The capture race continued until Silver cleared the southwest enough to force a goal. Gold's other key mistake was in continuing to race after capturing the silver camel; on his next turn, Gold could have moved his elephant from g6 to f5, and used his other two steps to minimize losses in c3, which his elephant could have defended on the following turn. The capture race would have then ended in a position not unfavorable to Gold, who would have been strong in the east. Allowing Silver to continue the cleanup in c3 was fatal for Gold, whose own captures didn't matter once a silver rabbit approached a thin goal line.

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8 Arimaa rs.svg Arimaa rs.svg 8
7 Arimaa ds.svg Arimaa dg.svg Arimaa rs.svg Arimaa cs.svg Arimaa rs.svg 7
6 Arimaa dg.svg Arimaa hs.svg Arimaa rg.svg Arimaa ms.svg 6
5 Arimaa rs.svg Arimaa eg.svg Arimaa hs.svg 5
4 Arimaa es.svg Arimaa mg.svg 4
3 Arimaa rg.svg Arimaa cg.svg Arimaa rg.svg Arimaa rs.svg 3
2 Arimaa hg.svg Arimaa rg.svg Arimaa ds.svg 2
1 Arimaa rg.svg Arimaa rg.svg Arimaa rg.svg 1
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Goal threats trump capture threats.

In the position at left, from this game, each side is threatening goal, but Gold's threat is currently stronger. Silver is to move, and must stop the d6 rabbit; merely freezing it would not be enough, since Gold could unfreeze and unblock it with Dc7s rd7w, leaving two steps for goal. If Silver used her elephant to stop this goal, her own threats in the east would be gone. Silver's best option may be mg6ww Rd6s me6w; this would keep Silver's eastern threats intact, delay Gold's threats, and even threaten the c7 dog. The gold elephant would likely then step to c5; if Gold used his other three steps to capture the g3 rabbit, the silver elephant could capture the gold camel in f6, and then defend c6 before Gold could capture anything there. With the gold camel gone, the silver camel could lead a new, stronger attack in the east. If Gold foresees this, he will likely leave the g3 rabbit alone, and use his last three steps to push the silver camel off of d6, thus reestablishing full control of the c6 trap. Gold would have capture threats, but not yet a one-turn goal threat, and the race would continue.

When one loses home trap control, it is probably too late to start a race. Instead, the defender might protect material with the elephant while building towards a slower counter-attack.