Infinite Levels

In a world ruled by those called adventurers.
Two portals to other worlds opened in the center of an ocean. These gates rank SS. They call it the White and Black Gate. The white gate is home to another world where magic and fantasy exists. Some call it the neutral gate. Many other gates spawn even to this day. The Black gate is a home to many atrocious monsters that can be a danger to all humanity if they are not kept under control. This world has their own set of heroes, however. They protect us from the monsters.
They are who we call adventurers or sometimes called 'Hunters'.
I'm Ethan Adler. I'm the son of one of the most powerful adventurers to ever exist within our world. They called him 'Silver Flame'.
Why did Father leave me and my sister?
Why did he choose to go into an SS rank gate?
Why...
The gates brought us both wealth and fame to those who explore it but the truth of why those gates appeared is much more ominous than one might think.
--Note that this novel is in the process of being rewritten and edited