I wonder what would happen if two users of Complete Arsenal would fight each other? With their Flawless Precognition, Flawless Indestructability, Absolute Combat and Absolute Immortality it doesn't seem for me one can defeat the other one.
In my opinion, when such situation happens, two users enter perfect state of harmony and power balance when they reached the ultimate apex and can't defeat each other. It would be interesting to see this kind of combat, wouldn't it?
Nonetheless, I doubt about one thing. As users of CA, both of them posses legendary Nonexistence. How would their fight go in this light when both of them can erase each other instantly? Yes, one can oppose Nonexistence with Meta Existence but would this be possible? Readd yourself once you were totally erased.