The apocalypse arrived, and Irving was betrayed and killed by his own girlfriend. After his rebirth, he was chosen by the Will of the Blue Star to be an internal beta tester of the Shelter Game, starting with a [Tenfold Drop Rate] and becoming a [Necromancer]! Ferocious and brutal exotic beasts are all tamed by him, gradually forming a powerful "Exotic Beast Legion" under his command! Building sanctuaries, hoarding supplies, upgrading outer walls, setting traps... Constructing the most powerful fortress in the apocalypse! "Since I have been given a second life, I will trample those who've betrayed me once under my feet!" ... When the Dark Lord descended, Irving's shelter had become the strongest on the Blue Star! "You evil creatures, dare to covet Blue Star?" "Come on! Let me show you what true despair is..." "Remember, from now on, Blue Star is under my protection! Got it?"
Pretty interesting novel overall. I just have huge problem with his shelter. Essentially it's fundamentally just shallow shelter no matter how many floors he has. After all first floor is near surface, and after that you just have floor after floor going down. Making mc's whole shelter protected only by about 10m of soil and some concrete. Not to mention his food production, home etc. are all at the topmost levels. Proper shelter would be at appropriate depth for defense and heat management, then just keep it at one floor so it's easy to navigate and expand sideways.