Maybe 1 on 1, but 5 on 5, and the angels don't stand a chance.

Firstly, an archangel might not lose in melee combat against a monster, given the right circumstances. Secondly, what's the question? THE BEST creature, the best, do you understand? I'm not sure you would put a monster in first place as the best. The archangel has a speed of 18! Only the phoenix is faster, it can fly, has stable damage, attack, and defense of 30. Increased morale, hatred for demons, and resurrection as well. No matter what you take, no one can boast such abilities, whether it's a titan, a monster, or a dragon; the superiority is obvious, plus some other abilities that I've already written about – try pitting it against the same monster and see what damage the archangel and the monster inflict, given its 80% penetration.