Strategy Game Summons for Hegemony from Another World

The mediocre protagonist in real life one day suddenly reincarnates into an exiled aristocratic child in a different world of swords and magic, only to find that he has a system that can summon the people he wants from the game he loved in his previous life. So how can he use this system to survive in this dangerous different world? This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.