MCU: Barbarian Gamer

Hello, Author here - I'm absolutely horrid at writing synopsis as I've recently found out. I've been trying to write one for the past hour but I just can't get it right. So, I thought instead of giving too much away or giving too little details about the book, I'd just tell you what you're in for. Basically, the MC is reborn into Marvel, more specifically an MCU timeline that has been merged with the McAvoy X-Men timeline. MC will be a Mutant who's mutant power is that anytime he wants, he can travel to an unusual world that is reminiscent of the Dungeons from the Gamer series, and after he kills enough Mobs in the dungeon, a boss spawns just like in the Manhwa. Except these bosses correlate to a boss from my favorite game: Dark Souls 3. Obviously he also has a system but it'll be a bit different than the system from the Gamer. It'll have a class in it, for one. Which for the MC, is obviously a Barbarian. Either way, this is my first fanfic, so I hope to not disappoint too much!