User blog comment:B214/Question and Answers 6/@comment-5.36.182.185-20161001040526/@comment-1359322-20161001101139

At his prime and with the right weapon, most likely yes.

Though seeing how Serafll, Ajuka and Sirzechs are, it's hard to see Vasco beating them, with the 2 requirements mentioned. Then again the current Yondai Maou might be more powerful than the original ones.