User blog comment:Hitsuji Mamoru/FGO-style Servant Creation Room/@comment-28209103-20170121092930/@comment-30121804-20170122034904

Interesting. By utilize his power of philosophy to influence the mind of normal human (brainwash?), he can have an army of any size as long as the area's population allow. And with power of Reality Marble that denies supernatural definition (servants' skills that required mana?), his army of men can fight on the same ground as servants. Though I can imagine a blood bath if they face an Evil servant with extradinory battle prowess like Attila or Regend. (´Д` )

Gameplay aside, I think that the only way for him to win a holy grail war is to trick enemy servants into his territory and then swarms them with his army and hope for the best.