User blog comment:Ixarising/High School DxD Dream Battle/@comment-65.8.88.18-20140216042454/@comment-98.26.119.147-20140216042939

Cao Cao has the strongest longinus and has fine tuned it very well. Dulio Gesualdo has the second strongest longinus but is very lazy so we don't really know the extent of how strong he is but he was the strongest exorcist and has the powers of an angel which also adds to his magic power.

So I would go with Dulio.