Spawn's mission should have become easier with the return of his powers. But unfortunately for him, there have been those who have been waiting, planning, and building up their armies. Knowing that, at some point, they will have the opportunity to strike back at Al Simmons.
When Gunslinger looks into a mirror. He no longer sees a face that is his own. Every day he spends in the present makes him realize that he may never have the opportunity to return home and set things right.