Basically novels with a level system, game interface, skill acquisitions (skill books and related), a betrayed MC, ruthless and antihero MC, in a modern apocalypse setup, and floor climbing stages. Preferably No Harem, But if there are a novel that has Harem yet it is amazing, it's acceptable too. Novels like: Seoul Station Necromancer Reincarnator Second Life Ranker Kill the hero Human Emperor