The rolling numbers are just as important as the portraits. During normal combat as the DMW spins and stops if certain numbers are lined up you gain special status.
666: All attacks become critical hits for 20 seconds
555: Physical Guard for 15 seconds
444: 0 AP Consumption
333: Magic Guard for 15 seconds
222: 0 MP Consumption
111: Invincibility for 15 seconds
77*: 0 MP Consumption for 15 seconds
7*7: Physical Guard for 15 seconds
*77: Magical Guard for 15 seconds
7**: 0 AP Consumption for 12 seconds
7: 0 MP consumption for 12 seconds
**7: Endurance for 20 seconds
The big benefits come from matching numbers in modulating phase.
777: Zack levels ups + Invincibility for 15 seconds
2 same (not 7): 1 level up for equipped # materia
3 same (not 7): 2 levels up for quipped # materia