Arimaa/browni vs. Fritzlein, WC2015


 * 1g [Gold setup]. Gold uses the 99of9 setup with cats behind the traps, which is a very common setup for Gold. Beginning in the center, the gold camel can quickly go to either wing.
 * 1s [Silver setup]. By contrast, Silver decentralizes his camel, threatening to quickly attack the f3 trap. A camel is not likely to stay in the middle, so one might figure to gain time by immediately placing it on the b- or g-file. Had Gold done this, however, Silver could have set up in such a way that would have forced Gold to either waste time moving his camel across or waste his camel's strength. The western silver cat is on b8 rather than c7; unlike a rabbit, a cat can advance and then retreat, so a cat near the edge might give one more flexibility.
 * 2g. The gold elephant blocks the silver elephant's e-file advance.
 * 2s. Silver's western horse defends c6, while his eastern horse starts advancing for a potential attack on f3.
 * 3g. With the silver camel in the east, it is safe for Gold to advance a horse towards c6.
 * 3s. The silver elephant advances through the middle, threatening the western gold cat and horse. The silver camel steps forward, setting the stage for an MH or EMH attack in the east.
 * 4g. The western gold horse is aiming for a6, from where it might later get onto b6. Meanwhile, the h-file rabbit advance is meant to take up space and thus slow Silver's eastern attack. An early rabbit advance is double-edged, perhaps making it somewhat harder for the opponent to attack one's home trap, but easier for the rabbit to be pulled further up and threatened in the opponent's home trap. Gold figures that a head-start on a western attack is worth more than a rabbit. Gold could have moved his camel east to defend f3. However, the rabbit advance now makes it more urgent for Gold to attack in the west, as he may soon be down a rabbit.
 * 4s. Silver pulls the gold rabbit further up the h-file. Gold is not yet positioned for a trap attack, so Silver may have time to capture the rabbit.
 * 5g. Set on a western attack, Gold does not move his elephant east to threaten the silver horse and camel.
 * 5s. Silver continues with the rabbit pull, threatening to capture it on the next turn. Silver flips the rabbit onto g5 rather than h6, partly to protect his horse and camel from the gold elephant.
 * 6g. Gold proceeds with his attack, threatening to take the b6 square on the next turn. The alternative was to pull a rabbit on the a-file, but Gold is well behind in any rabbit-pulling race.
 * 6s. Wanting to keep his own horse on b6, Silver freezes the gold camel.
 * 7g. The gold elephant goes to d6, ensuring that no friendly piece will be captured in c6 or forked on d6. Gold also advances a dog, which will likely go to c5.


 * 7s. The c2 cat is hanging, but capturing it would leave the silver elephant decentralised and allow Gold to make progress around c6. Silver decides against this trade-off, instead finally capturing the rabbit. He could have flip-captured the rabbit and not moved his horse to the f-file, but feels confident since Gold would face a camel loss if the gold elephant were to move east. On f5, the silver horse is now closer to both gold dogs.
 * 8g. Gold advances his dog to c5, which might allow his elephant to step into the trap for a pull-and-replace. Another gold rabbit advances on the h-file, to slow down any eastern counterattack. Now that Gold's attack is underway, Silver will not have time to pull another rabbit.
 * 8s. Pushing the camel away slows down the attack, while Silver looks to get a counterattack going on the other wing. Silver could have framed the dog, but the frame probably wouldn't have held, and a dog frame is usually not worthwhile if the framer's elephant can't rotate out. Another option for Silver was to occupy c6 with a rabbit, which would have prevented Gold's next move; Silver would have also needed to occupy two other squares adjacent to d6, so that the gold elephant couldn't flip the rabbit out of c6. Silver might not want to commit so much to defense, as he has potential for a strong eastern attack.
 * 9g. A pull-and-replace gets the gold horse onto b6. This move is reversible, but Gold would win the repetition fight.
 * 9s. Silver plays a delaying move while gaining space on the a-file. This will not regain b6, since another pull-and-replace is possible.
 * 10g. Gold plays the pull-and-replace, once again creating a new position and winning a potential repetition fight, as Silver would need four steps to undo this.
 * 10s. Silver moves his horse to c5, partly to avoid a flip that could unbalance his forces and leave him weak in the west. The silver elephant freezes the gold camel and horse, and the a-file rabbit advance blockades the camel in place even if it is unfrozen.
 * 11g. In clearing c4, Gold prepares to push the silver horse toward c3, which would create a double-threat in the west. Though frozen, the b6 horse remains an asset for Gold, as it allows for potential threats in c6.
 * 11s. The eastern silver horse moves to e3, potentially threatening both c3 and f3.
 * 12g. Gold could go after the e3 horse and likely exchange horses, but Silver would capture first and then threaten the gold camel. Gold thus keeps his elephant beside c6, pushing the other silver horse toward c3.
 * 12s. Silver defends c3 and c6, while threatening to attack c3 or f3.
 * 13g. Gold defends c3, and replaces his elephant on c5. If the silver elephant were to now step east, this would free the gold camel to threaten the silver horses in c3.
 * 13s. Silver threatens a false protection capture in f3, while setting up a dog frame on c6.
 * 14g. Gold moves his eastern horse away from the silver camel, and clears c3 for a potential horse capture.


 * 14s. The b4 horse faces capture in c3. If it runs to a4 or b2, the gold elephant will go east to threaten Silver's camel and other horse. The silver elephant will then have to leave b5, and the gold camel will strongly threaten the horse. While the horse is on b4 and the gold camel is frozen, however, the gold elephant must stay in the west to protect the c5 dog. Seeing potential for a strong eastern goal threat that will force Gold to give up his horse and dog, Silver allows his own horse to be captured. The cat steps east to prevent any gold rabbit from sneaking down the h-file.
 * 15g. Gold makes the horse capture.
 * 15s. Silver creates a one-turn goal threat which Gold will need two steps to block. The silver camel cannot immediately be threatened, as Gold would need three steps for that.
 * 16g. Gold blocks the goal and moves his elephant east, to threaten the remaining silver horse if not the camel.
 * 16s. The silver horse could push the gold cat to f3 and then go to f1, almost forcing goal due to an "air bubble" on g1. However, the gold cat could then freeze the rabbit on h2; on the next turn, the gold elephant could go to f2, freezing and threatening the silver horse. The silver elephant would likely not come east to defend, as that would leave the c6 trap highly vulnerable. Silver thus immediately plays for material, forcing a dog capture unless the gold elephant abandons the southeast. The camel step ensures that Silver could force goal in two if the gold elephant went north. Gold must concede his horse and dog.
 * 17g. Gold threatens the silver horse.
 * 17s. Silver captures the dog and threatens the horse.
 * 18g. Gold captures the silver horse.
 * 18s. After this trade the material balance is roughly equal; the question is which side will get an advantage in free pieces. Both camels are exposed.
 * 19g. Gold chases the silver camel while retreating his own camel.
 * 19s. Silver could force a camel trade by pulling the gold camel to a5, but Gold would capture first and then have a head-start on an eastern attack. Silver instead moves to defend his own camel, reasoning that Gold is not likely to establish a solid hostage position with a silver rabbit burrowed on h2. Furthermore, Gold will now need two steps to save the f4 horse.
 * 20g. Gold retreats his horse and protects the f2 cat, which might have otherwise been dislodged, in which case the horse would have been captured in f3. He steps his camel back toward c6; it could have taken another step, but then Silver would have needed only three steps to threaten it in c6.
 * 20s. This will force a camel capture, as the gold elephant is too far away to defend in the west. Gold can capture the silver camel in return, but capturing first could be a significant advantage for Silver on this depleted board.
 * 21g. In pulling the silver camel, Gold steps his elephant north, so that the camel cannot be unfrozen. Gold advances a rabbit to h4, perhaps eyeing a goal threat after the camel exchange.
 * 21s. Silver makes the camel capture. He could have instead saved his own camel, but this would have left the gold camel to dominate the west.
 * 22g. With the camel trade, Gold now has the uniquely strongest non-elephant piece on the board, and a potential goal threat on the h-file. However, Gold is weak in the west and likely will not have time to capture Silver's advanced rabbit in the east. It is unclear who is objectively ahead at this point.


 * 22s. Silver moves his elephant to d3, blocking the gold horse so that a silver dog can easily advance in the west.
 * 23g. Gold could now create a one-turn goal threat on the h-file, but would have to decentralize his elephant. Gold instead moves his elephant toward the standard attacking squares, and uses his other two steps to defend c3.
 * 23s. Silver advances a dog into c3, and Gold cannot block both c2 and b3. Silver would not have had time for this dog advance had Gold threatened a one-turn goal on 23g.
 * 24g. Gold moves toward an attack on c6, or possibly a dog hostage beside c3. Gold could have gone for an eastern attack, but may feel that Silver is ahead in a potential opposite-wing attacking race. With his elephant and horse in the west, Gold might limit further advances by Silver.
 * 24s. To threaten the horse without risking his dog, Silver moves his elephant onto c3. He must now carefully watch the surrounding area to ensure that his elephant cannot be captured.
 * 25g. Gold moves his dog east, to prevent a goal attack and threaten the advanced silver rabbit. He steps his elephant west to prevent a horse capture in c6. Further maneuvers in the west will be tricky, as Gold does not want to allow a capture in c3, and does not want his horse taken hostage beside c6.
 * 25s. To slow any advance by the gold horse, Silver advances four pieces in the west.
 * 26g. Gold now creates a one-turn threat to the advanced rabbit.
 * 26s. The silver elephant finally steps off of the trap, pushing the gold horse west and then north to keep it away from the silver dogs. This does give the gold horse free steps toward c6, but Silver is not worried about an attack there.
 * 27g. Gold defends c3, and tries to block an a-file rabbit advance by Silver.
 * 27s. Silver defends his rabbit, placing his dog on f2 to keep it far from the gold elephant, and to create a goal threat if the gold dog moves.
 * 28g. Gold attacks c6, but Silver can easily take the horse hostage.
 * 28s. This hostage gives Silver a large advantage, as the gold horse is no threat to the two silver dogs, and the one gold dog is effectively stuck defending goal.


 * 29g. Gold advances his c-file rabbit, but it is blocked from goal. Any attempt to move the silver rabbits could backfire, as those rabbits might end up threatening goal on this depleted board. Gold may be aiming to rotate his elephant out of hostage defense, and hoping that a rabbit can hold c5.
 * 29s. Silver advances his e-file dog and f-file rabbit, perhaps aiming for a goal threat in the center or an attack on c3.
 * 30g. Gold could now advance his cat to d6 and step his elephant east, but this would open up more space for the b5 and f5 rabbits to threaten goal. Gold does his best to block those rabbits, moving his cat east rather than north. He does not move his dog, as the h3 rabbit might then reach goal.
 * 30s. Silver now has a rabbit frame, and his own c5 rabbit is five steps from goal.
 * 31g. The gold cats attempt to block both the c5 and f5 rabbits from goal.
 * 31s. Still eyeing a central goal threat, Silver moves a rabbit to d5 and another onto c5.
 * 32g. Gold threatens the c5 rabbit with capture in c3, and moves a rabbit to d4 to block the d5 rabbit.
 * 32s. Silver creates a one-turn goal threat on the e-file.
 * 33g. Gold blocks the goal and tries to relieve the rabbit frame in c6.
 * 33s. Silver could capture the d3 rabbit, but does not want the c6 rabbit to get out of the trap and threaten goal.
 * 34g. Gold now creates a one-turn goal threat, with the rabbit that Silver chose to pull rather than capture.
 * 34s. Silver blocks the d5 rabbit in place, and steps his cat east to avoid immediately losing it in f6. He does advance a rabbit, which could now be captured if gold advanced his dog, but in that case Silver could reach goal first.
 * 35g. Gold reopens the one-turn goal path.
 * 35s. Silver blocks an e-file goal and defends f6.
 * 36g. Gold gives up his framed rabbit, but threatens a dog capture or goal.
 * 36s. Silver blocks goal and threatens goal.
 * 37g. Gold moves his elephant east, to stop a goal and threaten four different silver pieces.
 * 37s. Silver captures a cat in c3, which Gold left undefended. Silver also freezes and threatens the e6 rabbit, which could have otherwise reached goal on the next turn.
 * 38g. Gold could now capture the e4 rabbit and threaten the d3 dog, but would lose his horse and then face an active silver elephant. Gold thus creates a one-turn goal threat through f6, while freezing Silver's e4 rabbit.
 * 38s. Silver delays the goal by occupying f5, and reestablishes his own one-turn goal threat.
 * 39g. Gold captures the f5 rabbit and again reestablishes a one-turn goal threat while stopping Silver's, as the e4 rabbit would be frozen if the dog stepped aside.
 * 39s. Silver defends f6 and captures the gold rabbit which threatened goal.
 * 40g. Gold captures the dog and steps his cat south to make it harder for the silver rabbit to advance.
 * 40s. Not facing a one-turn goal threat, Silver finally captures the horse, activating his elephant.
 * 41g. If Gold were to now capture a rabbit in f3, Silver could pull the b4 rabbit east, threatening it in c6 while also threatening goal. Gold thus pushes the e4 rabbit west, to block the silver elephant from c4 or d4.
 * 41s. With no way to save his c4 rabbit, Silver moves his elephant east.
 * 42g. Gold blocks the silver elephant from e4 and g4.
 * 42s. The silver elephant returns to the west and threatens the gold cat.
 * 43g. To prevent a western goal, Gold moves his elephant to d3.
 * 43s. The silver elephant moves to e3, creating a one-turn goal path for the g4 rabbit.
 * 44g. Gold advances a rabbit into f3, to block the goal and to block the silver elephant from moving through the trap.
 * 44s. Silver blocks an f-file rabbit advance by Gold, and ensures that his own f4 rabbit could not be frozen in place.
 * 45g. Gold blocks the silver dog from g3, but his elephant advance leaves him even more vulnerable at home.
 * 45s. Silver captures the hanging cat.
 * 46g. Gold could capture the f4 rabbit in f3, but then the d5 silver rabbit could immediately reach goal. Gold tries to freeze or block all silver rabbits which threaten goal, but Silver can move his elephant to e3 and keep the goal threats coming.

Gold then resigned the game without even waiting for a 46s, as his position was hopeless. Any attempt to threaten goal would have resulted in the advanced gold rabbit being captured or a silver rabbit having an immediate path to goal. Despite the subsequent tactical threats, Gold was perhaps strategically lost by 28s, as he had no goal path in the west and would have been beaten to goal in the east had his dog advanced.