Tunnel Rat
Walrus King
Milo lives in a steel cave within a man-made mountain of steel and concrete, spending his days repairing the machinery that keeps the habitat livable and tinkering with prosthetics that help his twisted body move through small tunnels and air shafts. He is as much discarded machinery as the equipment he keeps running — an escaped lab experiment living in a hole. Given a chance at being someone different in the World of Genesis, a full-dive VRMMO that has become the new frontier, Milo must decide if he will become a hero and live in the sunlight. Ancient mysteries left by races that delved deep and stayed below await discovery, and maybe only a tunnel rat can find them.
Progression: Central, explicit LitRPG progression drives every arc. Tunnel Rat is built on a detailed World System with explicit levels, class advancement, skills, and stats analogous to cultivation realms. Milo advances through measurable thresholds: character level, skill ranks (science, magic tinkering, thievery, ninja abilities), system-granted abilities and perks, and item invention that unlocks new tiers. Progression is quantified and gated — World Bosses, dungeon clears, wizardly duels, assassin games (Surprise!), and dwarven engineering challenges provide XP and loot that push rank advancement. The habitat-to-Genesis pipeline mirrors realm breakthrough: discarded lab-rat → Genesis novice → shadowport operative → were-rat/Tallsqueak champion → dungeon engineer. Each volume raises the power ceiling (Genesis system, dwarven high explosives, AI Wally, corporate/crime intrusions) and requires Milo to invent, level, and master new system mechanics to survive. The narrative explicitly labels LitRPG progression as its core hook: 'detailed world and System, science skills, magic tinkering, item invention.'
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