[Nightengale]

Every Servant, at his element, has a chance of defeating another. Furthermore, stats are only circumstantial to their base physical strengths, significantly discounting things like aptitude and mentality.

I mean, Archer has crappy stats, but as someone capable of materialising Noble Phantasms, using them to a degree of expertise, and lastly, capable of turning them into extremely potent bombs, the virtue of that instantly already puts him up there as one of the Servants who can actually chip off lives from Heracles.

I mean, let's assume Gilgamesh has a D in every single stats of his. He would still wreck every other Servant because his stats has literally almost no relevance to the way he likes to fight, and that because his Noble Phantasm is the key maker for his strength. Archer is the same way, but to a lesser extent.

This is where they are different from Servants like Heracles, Saber or Zero/Berserker... where their stats are clearly extremely essential to the way they fight, because their NPs are just an extension to their forte as an all-rounder combatant.