Arimaa/Omar vs. Fritzlein, 2005 Postal Championship

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Played over four months, this game ultimately gave Fritzlein a perfect 10-0 record in the 2005 Arimaa Postal Championship. Had Omar won this game, he and Fritzlein would have tied for first with a 9–1 record. With the ultra-slow time controls, a postal game allows one to work through many different sequences before deciding on a move.

Game

  • 1g: Omar uses a variation of the 99of9 setup, placing dogs behind his traps. Since a dog cannot be pushed aside by an enemy dog, this alignment limits the ways in which a trap can be attacked. A dog might later advance through a trap and be replaced by a rabbit or cat.
  • 1s: Fritzlein chooses the classic 99of9 setup, with cats behind the traps. This initially leaves his home traps somewhat more vulnerable than Omar's, as a cat could be displaced by an enemy dog. However, "cats behind the traps, dogs back and center" affords more flexibility overall.
  • 2g: Omar aggressively advances his elephant four squares, threatening to capture a cat or flip the camel.
  • 2s: If Fritzlein were to now advance his own elephant four squares, he would concede a cat but also threaten a dog. Any such capture would use all four steps and create further threats, so this could begin a race with an unclear outcome; Fritzlein would initially capture a dog for a cat, but Omar might still have a first-move advantage. Declining such a race, Fritzlein defends both home traps and shields his camel.
  • 3g: Due to the risk of an elephant smother, Omar does not advance his elephant further. It would make sense to keep the elephant on e6 only if Omar were planning to quickly advance another piece, which would then be protected from capture in f6 but might still be taken hostage. Not ready to begin a multi-piece attack, Omar steps his elephant back a square, and uses his other three steps to develop at home. Omar could have saved time by advancing his elephant only two or three squares on 2g, while also stepping one or both of his horses forward on that turn.
  • 3s: Fritzlein advances his elephant, stepping it east to face Omar's camel. Fritzlein's western horse defends the c6 trap, blocking Omar's horse from b6.
  • 4g: Omar drags Fritzlein's eastern horse towards the f3 trap. Fritzlein can easily prevent a capture, but Omar hopes to build a strategic advantage by putting Fritzlein on defense.
  • 4s: Fritzlein decides to free his horse before it can be taken hostage. Fritzlein uses his elephant to unfreeze the horse; he could have advanced the h7 rabbit to h5 and unfrozen the horse that way, but the rabbit would have then been exposed. Another option was to step the g7 cat forward, but Fritzlein preferred to return his horse to g6, which could not have immediately happened had the cat been on that square.
  • 5g: Omar moves his horse away from Fritzlein's elephant. So far the opening has been defensive, with non-elephant pieces retreating from threats.
  • 5s: Fritzlein further decentralizes his elephant to pull a rabbit on the h-file. Later Arimaa theory would frown on this, but in a defensive game it may have seemed logical, as a rabbit cannot retreat homeward. Fritzlein could have instead used his elephant to push Omar's e3 horse to d3, thus placing both of Omar's horses in the west, where Fritzlein's camel could have then gone to face them. With no horse in the east, Omar could have been vulnerable there also, and Fritzlein might have gotten strong threats on both wings. Not keen on early trap attacks, Fritzlein prefers the short-term rabbit capture threat.
  • 6g: Omar moves his elephant west to make a bigger threat. Fritzlein can hardly continue hunting an eastern rabbit when his western horse and potentially the c6 trap are in jeopardy.
  • 6s: Rather than moving his western horse and thus immediately opening up b6, Fritzlein centralizes his elephant and threatens to flip Omar's e3 horse.
  • 7g: To centralize his own elephant, Omar pulls the b6 horse twice rather than flipping it. Omar could have pulled the horse to b4 where it would have been harder to rescue, but prefers to have his elephant as centralized as possible, so as to limit Fritzlein's progress in the east.
  • 7s: Fritzlein gets his horse to safety. Continued pull-and-retreat play would slightly favor Fritzlein, since Omar has a rabbit exposed on h4.
  • 8g: In a somewhat more aggressive move, Omar advances a horse to a6; note that the horse advanced on the wing away from the enemy camel. This horse may pull a rabbit, but also threatens to take b6 in a potential trap attack. However, an elephant-horse attack usually requires support from other pieces, and Omar is poorly developed in the west; the c3 trap is even vulnerable to a counterattack. Omar might have done better to first move his other horse back to g3 and his camel to the middle, for flexibility.
  • 8s: Fritzlein does not immediately go after Omar's advanced horse, as a solid horse hostage can be tricky to set up. Fritzlein instead drags the h4 rabbit further forward, seeing that as a first threat which might in turn allow for an effective western threat.
  • 9g: Omar could use his horse to pull out Fritzlein's a8 rabbit, but a rabbit-pulling race would not favor Omar at this point. An attack on c6 would be too slow, allowing Fritzlein to capture the rabbit and perhaps even counterattack while still defending c6. Omar thus advances his camel in the east, perhaps intending to use his pulled rabbit to his advantage. An advanced camel is often at risk of being taken hostage, but a supporting flank piece can make this less likely. Increasingly vulnerable in the west, Omar advances a cat to help defend c3; this would not delay an attack for very long, but may give Omar time to attack first.
  • 9s: Fritzlein moves his elephant east to face Omar's camel. Whatever else is going on, an elephant must keep a constant eye on the enemy camel. Fritzlein also drags the rabbit to h6, now threatening it with one-turn capture.
  • 10g: Omar defends f6, placing his elephant on e6 rather than f5. In advancing his camel and dog, Omar moves toward a multi-piece attack on f6.
  • 10s: Unable to capture anything in f6 as long as Omar's elephant defends, Fritzlein moves his camel west, replacing it with a cat on f7.
  • 11g: Omar's horse retreats empty-handed, but his camel advances undaunted, creating an immediate capture threat in f6. With a friendly rabbit on h6, the camel can neither be frozen in place nor taken hostage on h6. No matter how things work out for Fritzlein here, this shows how an early rabbit pull might backfire.
  • 11s: Fritzlein defends f6, and clears room in his back ranks to push Omar's camel to g7, where it could be kept frozen and thus held hostage. Fritzlein's camel inches toward Omar's western horse, stopping on d6. With Omar's elephant on e6, this does jeopardize Fritzlein's camel, but only if Omar abandons his own camel as well as a rabbit.
  • 12g: Omar's camel could pull a rabbit onto f7 or g7, leaving Fritzlein no square on which to hold the camel hostage. Unfortunately, either pull would use all four steps, leaving the a5 horse to be confronted by Fritzlein's camel and threatened in c6. Not prepared to defend that trap, Omar further retreats the horse. He also steps his camel onto f6, conceding the camel hostage but making it trickier for Fritzlein to set up.
  • 12s: Fritzlein takes the camel hostage, albeit in a temporarily very awkward position. Before leaving one's elephant on a trap square, one must double- and triple-check that it is safe; since this was a postal game, Fritzlein had plenty of time for that.

    Fritzlein steps his camel west, no longer offering an immediate trade. With d6 empty, however, Omar's elephant can now flip Fritzlein's cat to e5.

  • 13g: Omar makes the flip, hoping to capture the cat and thus mitigate the hostage. Fritzlein likely cannot free his cat and also keep the camel hostage, as his elephant will now face capture if it finishes the turn on f6 without a piece on e7 or g7.
  • 13s: Fritzlein pushes the camel to g7; this freezes Fritzlein's horse on g6, but the horse couldn't have moved beforehand, as the elephant would have been lost. Stepping the d7 dog east may be a mistake, as this blocks a potential central hostage should Omar's elephant move to f5. Fritzlein could have slid his e8 dog and f8 rabbit west and pushed the camel onto f8, holding a hostage behind the trap while keeping his eastern horse mobile.
  • 14g: Omar pushes the cat to f4. Due to the risk of a camel fork, this move would have been untenable had Fritzlein left e7 clear. In that case, Omar could have simply pushed the cat south and moved his elephant back to e6; on e4, the cat would be frozen and threatened by a horse.
  • 14s: Fritzlein moves his elephant so that his eastern horse can advance.
  • 15g: Omar captures the cat. Omar would now like to swarm f6 and rotate his elephant out of hostage defense. Fritzlein would like to create a second threat and overload Omar.
  • 15s: Fritzlein must move his eastern horse, which could otherwise be flipped to f4 and threatened with two-step capture. Fritzlein advances the horse to g3, pushing back Omar's dog. Fritzlein may be trying to prevent a swarm of f6, but his horse is now exposed to immediate capture if Omar is willing to give up his camel. The horse could have instead stepped to the h-file, allowing for an initial swarm but standing ready to reassert control of f6 once Omar's elephant rotated out. Meanwhile, Fritzlein's other horse could have advanced in the west, facing no danger as long as Omar's elephant defended f6.
  • 16g: Omar abandons his hostaged camel to capture Fritzlein's advanced horse. While a camel hostage-holder often does end up trading a horse for the camel, Fritzlein could have done better here, especially since there was also a chance to capture a rabbit if Omar's elephant couldn't quickly return to the f6 trap.
  • 16s: Fritzlein will capture the camel; the only question is where his elephant should finish. Since Omar can immediately defend f6, Fritzlein must not keep his elephant in a corner on account of a rabbit. Fritzlein chooses f5 over e6, perhaps wanting to protect the eastern flank.

    Omar is now out a camel, but Fritzlein is out a horse and a cat. While this is close to even, tit-for-tat play will now tend to favor Omar, especially if he can capture Fritzlein's remaining horse. With no enemy camel to threaten it, Fritzlein's horse is now stronger than either of Omar's horses. From here, Fritzlein should play to get ahead, not easily giving up any piece.

  • 17g: Eyeing an elephant-horse attack against f6, Omar moves his elephant to e6, blocking a direct path to g6 for Fritzlein's camel or horse.
  • 17s: Perhaps not understanding Omar's plan, Fritzlein moves both dogs further east. With an active enemy horse nearby, a dog is unlikely to hold g6. Furthermore, it is often wasteful to have both dogs on the same wing. A dog in the west could have supported an attack on c3.
  • 18g: Omar advances his eastern horse and a dog behind it, preparing to take the g6 square. It would now be pointless for Fritzlein to flip the h6 rabbit into the trap, as the frame would immediately be broken.
  • 18s: Not confident about any western attack plan, Fritzlein moves his camel east, hoping to restore balance and perhaps take a new hostage.
  • 19g: Omar proceeds with an elephant–horse attack on f6, advancing a dog to keep the horse mobile. Once again, the h6 rabbit complicates a potential hostage for Fritzlein.
  • 19s: Fritzlein's camel moves further east, to threaten Omar's horse and rabbit. With no eastern horse of his own, however, Fritzlein may not be able to secure a camel-held hostage which would allow his elephant to leave.
  • 20g: Omar moves his elephant to f7, pushing Fritzlein's camel west and blocking the possible horse hostage.
  • 20s: Fritzlein moves his camel onto f6, setting the stage for an elephant smother if Omar's elephant remains on f7.
  • 21g: Omar retreats his horse, but his dog and rabbit are still at risk in f6. Omar could have instead pulled the camel north and pushed the cat east, centralizing his elephant and delaying any hostage by Fritzlein.
  • 21s: Fritzlein now threatens Omar's dog as well as his rabbit. Moreover, an elephant–camel attack on f3 is now possible.
  • 22g: Omar pushes a dog and pulls a rabbit, but this accomplishes very little. Fritzlein can still capture Omar's dog if Omar's elephant leaves the f6 trap.
  • 22s: Fritzlein sets up an elephant smother, which could be completed on the next turn if Omar does not move his elephant west. However, Fritzlein should have added a defender to the c6 trap; it is easy to neglect one area while focused on another.
  • 23g: Omar's elephant escapes, and has a one-turn threat to Fritzlein's b6 horse. A horse capture could make up for a dog and rabbit loss in f6.
  • 23s: Fritzlein elects to save his one remaining horse, rather than trade it for a dog and rabbit. Since Omar has no camel, Fritzlein's horse can only be threatened by Omar's elephant, and Fritzlein sees the value in having two pieces which face only one threat. Had Fritzlein taken this trade, Omar's horses could have then dominated the board.
  • 24g: Omar centralizes his elephant and saves his f5 dog. This was the one and only move that could accomplish both of those things, just as 23g was the one and only move that could free Omar's elephant and counter Fritzlein's capture threats.
  • 24s: Fritzlein could simply capture the h6 rabbit, but would have to end the turn with his camel exposed. Fritzlein thus moves his elephant to f5 and pulls the rabbit to g6, setting up a solid rabbit frame even if Omar defends the trap.
  • 25g: Omar once again defends f6 with his elephant. Anticipating a trap attack by Fritzlein, Omar defends f3 with four pieces. Omar also steps his western horse to the a-file, perhaps preparing to pull a rabbit. This would be far too slow, however, in light of Fritzlein's threat to f3. Omar could instead try to advance a horse through the middle and perhaps take c7 or f7.
  • 25s: Fritzlein frames the rabbit and thus pins Omar's elephant to its defense. Fritzlein advances his camel and may soon attack f3, but must watch the squares around f6 if he wants to keep the frame. If Fritzlein were to advance more pieces and leave his goal line thin, Omar's rabbit might threaten goal if it could get off of f6.
  • 26g: Fearing a camel-held hostage beside f6, Omar moves his eastern horse and dog. However, having one's horse passive in a home corner is not much better than having it held hostage beside an away trap.
  • 26s: Fritzlein develops in the east. The g-file rabbit advances to support its camel, not to threaten goal, as Omar's defense is sufficiently thick at the moment.
  • 27g: Omar proceeds with the slow plan of pulling a rabbit. This is not a sufficient response to Fritzlein's eastern threat.
  • 27s: Fritzlein rotates a dog forward with the idea of freeing his elephant to attack f3. With the enemy camel gone and the friendly camel patrolling the east, the dog can take f5, and a rabbit can hold g6. The framed rabbit couldn't retreat to f5 in any case, but Fritzlein's dog will block Omar from relieving the frame.
  • 28g: Omar retreats his e-file cat and dog. However, this gives Fritzlein's elephant a clearer path to e3, from where it could lead an attack on the f3 trap. On e4, the dog was not necessarily in danger unless an enemy piece began a turn on an adjacent square.
  • 28s: Fritzlein attacks the f3 trap, replacing his elephant on f5. Intending to move his own elephant to e3, Fritzlein advances a rabbit to h4 so that his camel can retreat if Omar's elephant comes to f4.
  • 29g: Omar blockades f3, but such a defense cannot hold for long. Moreover, c3 is now undefended.
  • 29s: Fritzlein threatens Omar's dog in f3 and cat in c3. The cat could be saved easily, but this would use up a critical step.
  • 30g: In three steps, Omar creates phalanxes to protect the pinned f2 rabbit and thus save his framed dog. This leaves a step to defend c3 and thus save the cat also.
  • 30s: The dog flip leaves Omar with only one way to defend f3. A horse flip would have likewise forced Omar's hand, but Fritzlein prefers to keep Omar's horse passive in the southeast.
  • 31g: Omar must move his elephant to f4 and thus give up his framed rabbit. Omar pushes Fritzlein's dog onto f5 rather than e4, so that it can't immediately join an attack on the c3 trap.
  • 31s: As Fritzlein planned on 28s, his h4 rabbit allows his camel to retreat. This may be the difference between the camel being taken hostage and the camel holding a hostage.
  • 32g: Fearing a cat fork, Omar moves his cat west. Fearing an elephant-horse attack on c3, Omar blocks Fritzlein's horse on the b-file. Fritzlein might move his horse through the trap, however, if his elephant goes to d3.
  • 32s: Fritzlein creates an immediate dog-capture threat, while also putting distance between his camel and Omar's elephant.
  • 33g: Omar defends f6 and shores up the southeast against any possible goal attack. If Fritzlein's camel again went south to attack f3, Omar's dog could become a strong attacker at f6.
  • 33s: Fritzlein threatens to frame Omar's dog in f6; this frame would likely force Omar to give up the dog, as Fritzlein's elephant could otherwise dominate the board.
  • 34g: Omar blocks the frame/capture and retreats his western horse out of immediate danger. Fritzlein's h4 rabbit again keeps his camel mobile.
  • 34s: In a mostly defensive move, Fritzlein's camel pushes Omar's dog up to the edge. A buried dog-by-camel hostage is not efficient, but Fritzlein's camel is out of danger, and Omar's dog is stuck in the corner. With no camel of his own, Omar might gain little advantage from this alignment.
  • 35g: Omar threatens a rabbit in f3, keeping his elephant on the g-file so that his horse can immediately return to g3 if pulled to g4. The dog step east might seem counter-intuitive, as it appears to leave the dog and the c3 trap more vulnerable. Had the dog stayed on d2, however, it could have been pushed to d3 and been unable to retreat.
  • 35s: Fritzlein defends f3, and begins to clear space for a dog capture in f6. Advancing a rabbit from f7 may not be wise, however, as this thins his back ranks and exposes yet another rabbit to possible capture in f3. Fritzlein could have instead advanced his horse; an elephant-horse attack on c3 might have outpaced any eastern progress by Omar.
  • 36g: Omar frames the rabbit and thus pins Fritzlein's elephant on e3. It is rarely worthwhile for an elephant to defend a mere rabbit; Fritzlein must soon either give up the rabbit or advance more pieces to the southeast and create a new threat there.
  • 36s: Fritzlein advances his cat, moving toward a possible swarm of f3. With the cat out of the way, Fritzlein pushes Omar's dog a square closer to f6.
  • 37g: Omar blocks the cat and rotates forward his horse, threatening an attack on f6.
  • 37s: Fritzlein finally establishes a one-turn threat to the dog. He also blocks g5 and thus g6. With rabbits now on g5 and h5, however, Fritzlein may face additional losses in f3 if his elephant is forced to leave.
  • 38g: Omar's eastern horse clears a path to g6.
  • 38s: Fritzlein again blockades g5, but Omar can continue to undermine that blockade and perhaps threaten more rabbits in f3. Fritzlein also moves his own horse from b6 to d6, perhaps hoping to advance it through the center. This leaves a hole in the northwest, however.
  • 39g: Omar steps his western horse toward the now vulnerable c6 trap; the horse could advance further, but must be careful about which square it ends on, as Fritzlein might be happy to give up his framed rabbit if he could create a second threat that would force the capture of a horse or dog. A cat advances to defend c3 and prevent a rabbit exchange. Rabbits advance in the east, to block enemy advances.
  • 39s: Fritzlein advances his horse on the d-file, aiming to either attack c3 or dig his rabbit out of f3. The horse takes only three steps, as it cannot be frozen on d3 but could be frozen on d2.
  • 40g: Omar can now move his elephant west without conceding an outright dog loss; if Fritzlein were to immediately capture the f8 dog, Omar's elephant could then capture the d3 horse even from d5 or d6. Omar moves his elephant to d4, perhaps intending to follow the horse.
  • 40s: Fritzlein gets his horse onto Omar's home rank, pulling a dog so that Omar can't immediately pull the horse up to d2.
  • 41g: Omar now attacks c6, as he could have essentially done a turn sooner. Omar clearly did not believe that such an attack would win a race, but a turn later he is now going for it.
  • 41s: Fritzlein snatches the dog and thus also activates his camel. He could have instead strengthened his western position by pushing the d2 dog east and the c2 rabbit south. Another option was to try to dig out the f3 rabbit, which might have beaten Omar's c-file rabbit to goal.
  • 42g: Omar captures a rabbit and advances his rabbit one step, setting up a goal on the c-file. Fritzlein is very weak in the west, and would only lose more pieces if he tried to block the goal on the back ranks.
  • 42s: Now facing a goal threat he cannot outrace, Fritzlein is forced to defend with his elephant, giving up the f3 rabbit and thus a potential goal threat of his own. Note that Fritzlein quickly lost two rabbits after capturing the dog.
  • 43g: With the c-file blocked, Omar must clear a goal path through a different file. If Fritzlein takes the advanced horse hostage on a6 and moves a dog onto c7, Omar will have no viable goal path, and Fritzlein will have a large advantage in free pieces. Attempting to block a horse hostage, Omar pulls a rabbit onto b6. Omar also defends the c3 trap, though in doing so he moves his c-file rabbit to the d-file, farther from the likeliest goal paths.
  • 43s: Fritzlein places a dog on c7, blocking a potential c-file goal even if his elephant goes to b6. He also inches his camel forward in the east; it is currently safe on f6, since the g5 cat can't be pushed east.
  • 44g: Omar retreats his horse and threatens a rabbit. However, Fritzlein's horse can defend c3 from behind, and Omar has given the rabbit free steps toward his own vulnerable goal line. Omar's horse could have instead pushed the dog off of c7, or better yet gone to c7 on the previous turn with steps to spare. This would have made it harder for Fritzlein to block a goal, if Omar could advance a rabbit in the west.
  • 44s: Fritzlein takes c2 and eyes d3, blocking Omar's elephant from that square. With his elephant on the d-file, however, Fritzlein could be vulnerable to a western goal attack.
  • 45g: Omar advances a rabbit and adds a defender to c3. With Fritzlein's dog on c7, the rabbit likely cannot reach goal without support from a horse. Omar's recent horse retreat may thus end up wasting multiple turns.
  • 45s: Unconcerned about Omar's c-file rabbit advancing further, Fritzlein uses all four steps to slide his camel onto g5, setting the stage for an eastern threat. Well-supported by rabbits, the camel will likely remain mobile even if Omar's elephant moves east.
  • 46g: Trying to stay ahead of a potential threat in the east or southwest, Omar advances his rabbit and dog in the west.
  • 46s: Fritzlein threatens Omar's eastern horse in f6. Fritzlein's elephant steps west, so that the rabbit frame can only be relieved from the side or from behind.
  • 47g: Omar's western horse relieves the frame, creating a two-turn goal threat. This will again force Fritzlein to prioritize defense.
  • 47s: There will not be a long-term horse hostage in the west, but by taking b6, Fritzlein limits the c6 rabbit's movement. It might have been better to push the horse onto a6, where it wouldn't have been right next to the c7 dog. The upside to pushing the horse onto b7 is that this will prevent Omar's elephant from pushing Fritzlein's dog west, which would open a c-file goal path.
  • 48g: Omar slides his dog, elephant, and rabbit, defending f6 and creating a one-turn goal threat on the d-file. The dog advance leaves Omar's b3 cat at risk in c3, though Fritzlein does not have time to capture it yet.
  • 48s: Fritzlein stops the d-file goal. He also advances a rabbit, gaining space on the f-file.
  • 49g: Omar moves his c5 dog south and pulls the c7 dog west, defending both western traps and reopening a possible c-file goal path.
  • 49s: In advancing his dog through c6, Fritzlein asserts control of that trap, threatening Omar's b6 horse and d5 rabbit.
  • 50g: Omar could avoid an immediate material loss, but might soon be overloaded. Perhaps fearing a southwestern attack, Omar freezes and threatens Fritzlein's advanced horse, setting up a possible capture race. Such a race would likely allow Omar to stay ahead in quantity of pieces.
  • 50s: Fritzlein accepts the horse trade, as defending c3 would have meant losing a dog. At this point, a horse trade is not a bad deal for Fritzlein, who will now have a camel and two dogs to Omar's one horse and one dog. Omar's remaining horse faces potential capture in f6, though Fritzlein's own rabbit currently blocks this.
  • 51g: In making the horse capture, Omar steps his elephant north to threaten Fritzlein's dog. The last dog step east momentarily activates the horse, but will not save it. Omar could have instead stepped the d5 rabbit east so that his horse could not then be frozen on f5. However, he likely did not want to leave his dog on d4, as this would have blocked a flip-capture of the c5 dog on the next turn; Omar wants to keep his elephant in position for a western goal attack. Omar might have done better to step his dog south, allowing for the flip-capture in c3 while also clearing another potential capture path that would force Fritzlein to be more careful with his camel.
  • 51s: Fritzlein could save his dog and rabbit in the west, but could then lose a rabbit in the east, in which case he would also lose the chance to capture the horse. Fritzlein thus goes for the horse capture.
  • 52g: Omar flip-captures the dog, keeping his elephant positioned for a western attack.
  • 52s: Fritzlein first captures the rabbit, which might have otherwise threatened goal. Omar's horse cannot be rescued on the next turn, so Fritzlein loses nothing by capturing the rabbit first. Now on c5, Fritzlein's elephant can defend his depleted west wing.
  • 53g: Omar's b3 cat captures to c2, clearing the b-file for a rabbit advance and perhaps strengthening Omar's home defense. Omar could have instead flip-captured the rabbit and then advanced a rabbit through the a-file, keeping his cat positioned to support a western goal attack.
  • 53s: Fritzlein completes the exchange and moves his elephant to d4, keeping Omar's dog in the east.
  • 54g: Omar threatens goal in the thinly defended west, and moves his cat back to the b-file.
  • 54s: Fritzlein blocks the goal and also temporarily blocks Omar's elephant from d6.
  • 55g: If he can push Fritzlein's dog onto e6, Omar may have a strong western goal threat.
  • 55s: Fritzlein brings his cat to e6, blockading e5 and ensuring that his dog could block a western goal. He does not move the dog on the fourth step, as that would allow for a capture in c6. Fritzlein's eastern goal defense is becoming thin, but his elephant and camel are well-positioned.
  • 56g: Blocked from the east and south, Omar's elephant steps north. Omar advances his d1 rabbit to d3, to defend c3 and also block a central goal.
  • 56s: Fritzlein unfreezes and advances his dog, blocking Omar's goal path and threatening an attack on c3.
  • 57g: Omar moves his elephant east to face Fritzlein's camel. At this point, however, piece alignment is of secondary importance. Fritzlein is poised for a western attack which Omar could not immediately match in the east.
  • 57s: Alert to the risks in both f6 and f3, Fritzlein moves his camel east. His elephant takes d3, again keeping Omar's dog in the east. Fritzlein is now well-balanced, with his dog and camel active on opposite wings and his elephant in the middle. Omar is poorly balanced, and must quickly defend in the west.
  • 58g: Omar temporarily defends c3, but leaves it vulnerable.
  • 58s: Fritzlein could now move his dog through c3, but doesn't want to lose material in f6 or allow Omar's b-file rabbit to advance further. Fritzlein thus pushes that rabbit west, and defends f6 from behind. Omar is running out of threats.
  • 59g: Omar advances his c-file rabbit, but moves his elephant further east, with the idea that he could capture Fritzlein's camel if Fritzlein were to immediately capture the rabbit. After such an exchange, however, Fritzlein could advance his e5 rabbit onto c3, creating a strong goal threat. In the endgame, a rabbit-for-camel exchange does not always favor the side capturing a camel.
  • 59s: Fritzlein defends and further advances his camel. Omar could take it hostage, but that would mean having his elephant in the southeastern corner while Fritzlein threatens goal in the west and center. Fritzlein's more centralized elephant could eventually join a goal attack, as there is no harm in losing a camel if one wins the game.
  • 60g: Declining the hostage, Omar moves his elephant west. Omar technically could have created a one-turn goal threat, but the rabbit would have then been lost immediately in c6. If not for Fritzlein's rabbit advance to e4, Omar would have had an additional step which could have created a stronger one-turn goal threat. Despite Fritzlein's positional advantage, this game could turn on a single step.
  • 60s to end: Omar is forced to block Fritzlein's h-file rabbit, and then block Fritzlein's camel from making a pull. This soon forces Omar's elephant to the goal line. Had Fritzlein miscalculated or just not noticed the one-turn goal threat after 66g, Omar could still have won. However, Fritzlein's position allowed him to defend goal and still keep his strong pieces on offense.

After this game concluded in June 2005, Fritzlein opined that the advantage had swung back and forth, and that Omar bungled a very strong position on 40g. By later bot analysis, however, Fritzlein held a continuous advantage after 21g. Defensively minded, Fritzlein often failed to see his own attacking potential. Nevertheless, he was the top player at the time, also winning the 2005 Arimaa World Championship.

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