2x2 (1-5)
2x2 diagonal difference
2x2 (1-9)
2x2 diagonal difference
2x2 mixed (+/-5)
2x2 diagonal difference
2x2 mixed (+/-9)
2x2 diagonal difference
2x2 mixed (+/-12)
2x2 diagonal difference
2x2 mastery (+/-15)
2x2 diagonal difference
3x3 with full row of zeros
zero row shortcut
3x3 with full column of zeros
zero column shortcut
3x3 triangular (upper)
triangular diagonal product
3x3 triangular (lower)
triangular diagonal product
3x3 (1-4)
3x3 cofactor boxes
3x3 (+/-4)
3x3 cofactor boxes
3x3 sparse (+/-6)
3x3 cofactor boxes
3x3 (+/-6)
3x3 cofactor boxes
3x3 mastery (+/-9)
3x3 cofactor boxes
2x2 realistic signed (no timer)
realistic 2x2 signs
2x2 realistic open (no timer)
realistic 2x2 signs
3x3 sparse realistic (no timer)
3x3 cofactor boxes
3x3 triangular realistic (no timer)
3x3 cofactor boxes
3x3 open challenge (no timer)
3x3 cofactor boxes