mitallast/diablo-js — reverse-engineered prompt

Build me a small browser game demo that feels like an old school isometric dungeon crawler, using plain JavaScript and an HTML5 canvas.

I want it to load in a simple index page and show an isometric level with floors, walls, objects, a hero sprite, monsters, textures, and basic shadows so it has that classic dark fantasy look. Keep the code as small and readable as possible, more like a minimal experiment than a full game engine.

Please include a map view that appears when I press Tab, and make the level use separate visual layers for the ground, walls, and objects. It should run locally in the browser without a complicated setup.

If useful, also include simple helper tools or notes for working with sprite sheets, textures, extracted game resources, and shadows, but the main thing I want is the playable canvas demo. Look up current browser canvas behavior online if you need to.