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The following positions address checker play in unlimited games. An unlimited game means a game that stands alone, where match score does not affect the decision. Tap the play you would make at the board.

The candidate plays are ranked by equity, the value of one play measured against the alternatives. Beside each play you will see W, GW and GL: Blue’s chances to win the game, to win a gammon, and to lose a gammon. Delta is the equity a play gives up against the best play.

The best play earns a green BEST badge. A play that gives up a little equity is an ERROR; one that gives up a lot is a BLUNDER. Have fun.

Unlimited Game - Position 1 of 10
How Should Blue Play 4-3?
Question board
Unlimited Game - Position 1 of 10
Answer: 18/14* 8/5
Answer board
PlayEquityDeltaW·GW·GL
18/14* 8/5BEST-0.444–40.7%·8.7%·24.1%
13/9 8/5BLUNDER-0.686-0.24232.9%·5.3%·16.9%
8/5 8/4BLUNDER-0.770-0.32731.6%·5.6%·18.4%
13/10 13/9BLUNDER-0.823-0.37931.7%·5.5%·20.9%
W = Blue Win%; GW = Gammon Win%; GL = Gammon Loss%
Unlimited Game - Position 1 of 10
Reasoning

Blue should attack to recover racing ground while strengthening the home board. Blue trails 163 to 122 pips, and White’s exposed checker on the 14 point offers a substantial gain rather than a small deep-board hit. Play 18/14* 8/5, sending White back 14 pips and covering Blue’s blot on the 5 point. Blue gains a second home board point, so the hit and the point support each other instead of competing for the roll. The remaining checker on the 18 point is exposed, which means the play still carries risk. Playing 13/9 8/5 loses 0.242 equity, a BLUNDER. Although that also makes the 5 point, it misses the immediate chance to reduce the large racing deficit and force White to enter.

Unlimited Game - Position 2 of 10
How Should Blue Play 3-6?
Question board
Unlimited Game - Position 2 of 10
Answer: 22/16* 13/10*
Answer board
PlayEquityDeltaW·GW·GL
22/16* 13/10*BEST-0.020–49.4%·17.3%·16.8%
22/16* 6/3*BLUNDER-0.181-0.16146.0%·15.7%·19.7%
9/3* 6/3BLUNDER-0.254-0.23442.6%·14.3%·17.9%
13/10* 9/3*BLUNDER-0.307-0.28742.2%·13.6%·21.1%
W = Blue Win%; GW = Gammon Win%; GL = Gammon Loss%
Unlimited Game - Position 2 of 10
Reasoning

Blue should attack the outside blots while bringing a back checker past White’s developing board. Blue trails 172 to 158 pips, and White has exposed checkers on both the 16 and 10 points. Play 22/16* 13/10*, hitting both and gaining 26 pips from the two White checkers sent back. Blue also moves the checker from the 22 point into the outer board while keeping the 8 point and the heavy 6 point intact. This is a disruptive attack, not a finished blitz, since Blue still has only one made home board point. Playing 22/16* 6/3* loses 0.161 equity, a BLUNDER. That alternative also hits twice, but the low inner hit gains much less racing ground and leaves White’s useful 10 point blot untouched.

Unlimited Game - Position 3 of 10
How Should Blue Play 5-1?
Question board
Unlimited Game - Position 3 of 10
Answer: 13/7*
Answer board
PlayEquityDeltaW·GW·GL
13/7*BEST-0.081–48.1%·13.7%·14.9%
8/7* 6/1*ERROR-0.116-0.03547.2%·14.2%·15.8%
24/23 13/8BLUNDER-0.199-0.11944.4%·10.4%·13.7%
24/18BLUNDER-0.201-0.12144.8%·9.1%·13.4%
W = Blue Win%; GW = Gammon Win%; GL = Gammon Loss%
Unlimited Game - Position 3 of 10
Reasoning

Blue should attack the exposed bar-point checker while keeping builders available. Blue trails 167 to 158 pips, with White split between the 1 and 7 points and only one made home board point on either side. Play 13/7*, taking a checker from the midpoint stack to hit on a point Blue would like to make. The 8 point keeps its spare, giving Blue nearby material to cover the hit or build another point after a miss. The alternative 8/7* 6/1* hits twice but loses 0.035 equity, an ERROR. It strips the 8 point and sends a second Blue checker deep to the 1 point. Here the useful single hit and better distribution outweigh the extra interruption supplied by a double hit.

Unlimited Game - Position 4 of 10
How Should Blue Play 5-1?
Question board
Unlimited Game - Position 4 of 10
Answer: 21/20* 20/15
Answer board
PlayEquityDeltaW·GW·GL
21/20* 20/15BEST+0.270–58.2%·13.7%·10.6%
21/20* 13/8BLUNDER+0.172-0.09854.9%·14.1%·10.7%
21/20* 8/3BLUNDER+0.096-0.17353.1%·14.3%·12.8%
21/20* 6/1BLUNDER+0.004-0.26650.7%·12.5%·14.0%
W = Blue Win%; GW = Gammon Win%; GL = Gammon Loss%
Unlimited Game - Position 4 of 10
Reasoning

Blue should hit and escape rather than remain exposed in White’s home board. The race is almost level at 143 to 142 pips, and White’s blot on the 20 point gives Blue a chance to gain substantial racing ground while leaving the anchor. Play 21/20* 20/15, sending White back 20 pips and carrying the attacking checker into the outer board. Blue leaves one checker on the 21 point, so the play accepts contact rather than removing every danger. Continuing to the 15 point is important because White’s nearby made points bear on the 20 point. Playing 21/20* 13/8 loses 0.098 equity, a BLUNDER. That version takes the same hit but leaves the hitting checker in the attacking area instead of completing the escape.

Unlimited Game - Position 5 of 10
How Should Blue Play 2-1?
Question board
Unlimited Game - Position 5 of 10
Answer: 13/12* 12/10
Answer board
PlayEquityDeltaW·GW·GL
13/12* 12/10BEST-0.614–37.2%·7.9%·24.0%
13/12* 8/6BLUNDER-0.715-0.10135.6%·7.9%·26.2%
8/5BLUNDER-0.733-0.11934.6%·7.8%·25.0%
6/3*BLUNDER-0.734-0.12034.7%·6.8%·24.0%
W = Blue Win%; GW = Gammon Win%; GL = Gammon Loss%
Unlimited Game - Position 5 of 10
Reasoning

Blue should attack for racing ground and then seek a safer landing point. Blue trails 154 to 145 pips, and the exposed White checker on the 12 point is a much larger racing target than the blot on the 3 point. Play 13/12* 12/10, sending White back 12 pips and carrying the hitter away from the immediate 5 shot from White’s anchor on the 7 point. The 10 point can still be hit, so this is not a risk-free escape. Blue retains the midpoint with two checkers and leaves the 8 point builders available. Playing 13/12* 8/6 loses 0.101 equity, a BLUNDER. It keeps the hitter on the more exposed 12 point while adding another checker to the already heavy 6 point stack.

Unlimited Game - Position 6 of 10
How Should Blue Play 4-2?
Question board
Unlimited Game - Position 6 of 10
Answer: Bar/23 13/9*
Answer board
PlayEquityDeltaW·GW·GL
Bar/23 13/9*BEST+0.110–53.1%·15.9%·13.8%
Bar/21 23/21BLUNDER-0.039-0.14948.9%·12.8%·13.6%
Bar/21 13/11BLUNDER-0.174-0.28446.3%·11.9%·18.5%
Bar/23 6/2*BLUNDER-0.228-0.33844.1%·12.2%·17.5%
W = Blue Win%; GW = Gammon Win%; GL = Gammon Loss%
Unlimited Game - Position 6 of 10
Reasoning

Blue should combine an anchor with an outside attack rather than defend passively. Blue trails 179 to 149 pips, with one checker on the bar and separate back checkers on the 23 and 24 points. Play Bar/23 13/9*, making the 23 point anchor and hitting White’s exposed checker on the 9 point. Blue gains nine pips from the hit, interrupts White’s development, and gives the entering checker immediate protection. The hit remains loose, but Blue keeps both home board points and the 8 point. Playing Bar/21 23/21 loses 0.149 equity, a BLUNDER. That alternative makes a more advanced anchor but leaves White free to use the next roll productively. Here the combination of security and immediate pressure is worth more than improving the anchor alone.

Unlimited Game - Position 7 of 10
How Should Blue Play 5-2?
Question board
Unlimited Game - Position 7 of 10
Answer: 21/14*
Answer board
PlayEquityDeltaW·GW·GL
21/14*BEST+0.149–55.3%·13.5%·14.4%
23/21 13/8BLUNDER-0.005-0.15449.0%·11.7%·9.2%
23/21 6/1BLUNDER-0.096-0.24646.2%·11.1%·9.4%
13/11 13/8BLUNDER-0.327-0.47742.8%·11.0%·23.1%
W = Blue Win%; GW = Gammon Win%; GL = Gammon Loss%
Unlimited Game - Position 7 of 10
Reasoning

Blue should attack and escape to turn the racing deficit into an advantage. Blue trails 152 to 141 pips, but White’s blot on the 14 point gives the checker on the 21 point a useful destination. Play 21/14*, moving past White’s home board and sending the exposed checker back 14 pips. After the roll, Blue has 145 pips to White’s 155 before White moves, a meaningful reversal rather than a small tactical gain. Blue’s checker on the 23 point remains a concern, and the hitter can be attacked, so the position still needs care. Playing 23/21 13/8 loses 0.154 equity, a BLUNDER. It improves the back checker’s location and adds a builder but leaves the racing opportunity unused.

Unlimited Game - Position 8 of 10
How Should Blue Play 2-1?
Question board
Unlimited Game - Position 8 of 10
Answer: 24/22 8/7*
Answer board
PlayEquityDeltaW·GW·GL
24/22 8/7*BEST-0.038–48.2%·12.7%·11.8%
22/20 8/7*ERROR-0.075-0.03747.7%·12.6%·12.9%
13/11 8/7*ERROR-0.092-0.05447.5%·13.5%·14.7%
8/7* 7/5BLUNDER-0.151-0.11346.1%·11.8%·14.5%
W = Blue Win%; GW = Gammon Win%; GL = Gammon Loss%
Unlimited Game - Position 8 of 10
Reasoning

Blue should attack the bar-point blot while securing the back checkers together. Blue trails 160 to 156 pips, with the back checkers split on the 22 and 24 points and White exposed on the 2 and 7 points. Play 24/22 8/7*, making the anchor and preventing White from simply covering the advanced blot. Blue keeps three checkers on the 8 point, leaving useful material to support the loose hit. White’s single made home board point makes this a reasonable moment to accept attacking risk. Playing 22/20 8/7* loses 0.037 equity, an ERROR. It takes the same hit but keeps the back checkers split and places one on White’s valuable 5 point without a partner.

Unlimited Game - Position 9 of 10
How Should Blue Play 6-1?
Question board
Unlimited Game - Position 9 of 10
Answer: 21/15 12/11*
Answer board
PlayEquityDeltaW·GW·GL
21/15 12/11*BEST-0.247–45.3%·9.6%·18.9%
13/12 13/7ERROR-0.325-0.07939.7%·4.9%·6.6%
13/7 12/11*BLUNDER-0.339-0.09241.3%·8.1%·13.5%
12/6 4/3BLUNDER-0.346-0.09939.2%·4.9%·7.4%
W = Blue Win%; GW = Gammon Win%; GL = Gammon Loss%
Unlimited Game - Position 9 of 10
Reasoning

Blue should escape the prime and use a hit to disrupt White’s next roll. Blue trails 139 to 134 pips, with the anchor on the 21 point behind White’s five-point prime from the 16 through 20 points. Play 21/15 12/11*, jumping a checker beyond the blockade while hitting White’s exposed checker on the 11 point. Blue leaves one checker behind, but the escape reduces the number trapped and the hit forces White to enter before moving another checker. The 4 and 6 points remain made to support the attack. Playing 13/7 12/11* loses 0.092 equity, a BLUNDER. That version hits the same target but leaves both back checkers behind the prime instead of using the available 6 to escape.

Unlimited Game - Position 10 of 10
How Should Blue Play 1-1?
Question board
Unlimited Game - Position 10 of 10
Answer: 24/20*
Answer board
PlayEquityDeltaW·GW·GL
24/20*BEST+0.148–52.7%·16.9%·12.5%
8/7(2) 6/5(2)+0.139-0.00853.5%·16.2%·14.7%
24/22 6/5(2)BLUNDER+0.050-0.09751.8%·13.9%·14.2%
24/23 6/5(3)BLUNDER+0.034-0.11451.2%·13.7%·14.0%
W = Blue Win%; GW = Gammon Win%; GL = Gammon Loss%
Unlimited Game - Position 10 of 10
Reasoning

Blue should attack White’s slotted 5 point while advancing a back checker. Blue trails 167 to 162 pips, and White’s exposed checker on Blue’s 20 point can soon become an important blocking point if left alone. Play 24/20*, using all four aces to hit and move the back checker forward. The hit sends White back 20 pips and interrupts development, although Blue remains exposed on the landing point. Making both the 5 and 7 points with 8/7(2) 6/5(2) is almost equal, losing only 0.008 equity. By contrast, 24/22 6/5(2) loses 0.097 equity, a BLUNDER. It makes just one new point and splits the back checkers without removing White’s immediate threat, achieving less than either leading plan.