Job transfer for all: equivalent call? I reverse cause and effect

The game has come to reality, monsters and beasts are rampant, and there are countless copies of the secret realm!
In order to resist monsters, human beings can only change jobs, become professionals, and upgrade crazily!
On the day of the job change, Lin Beiye, who is the number one genius in the school, changed his job to the Tiankeng profession [Equivalent Summoner]!
The stronger the summoned creature is! The more you pay the higher the price!
The more creatures are summoned! The more you...