The outcome is decided, and the difference is clear.
At the moment when the unharmed Osiris appeared behind Mo, the battle no longer needed to continue. If the former wished, he could easily turn the unspoken 'Disappearance of Time - True Illusion' into any powerful destructive spell, for he undoubtedly possessed such strength.
The reason Osiris did not do so is, of course, that having completely parted from his past and become the 'White Bishop,' he would not want to harm Mo no matter what.
From the start, there was no suspense in this battle. In front of Osiris, even someone as powerful as Mo could only barely withstand the initial round of spell bombardment. His precise and deadly counterattacks, whether it's the summoning creature [Scarlet Smoke] or the signature black magic [Blood Flash], posed no threat to Osiris.
