This is a playable demo, used only WebGL(1) it should work everywhere. Made to try some glass-like shaders and custom lighting.

Used 3d models from @flairetic, their sketchfab page.

Game has no sound.

Control:

Fullscreen button at right bottom, use mouse to click. Native version hotkey 0 or F11.
WASD or arrows - movement
Left-click to attack, Right-click and move mouseY to move center of camera focus.
Mouse scroll to zoom.
Esc or 1 to open menu.

Gameplay:

The gameplay is very minimal.

Player hit numbers in order, after number 3 if the player hits wrong or empty cube another character will spawn, while it exists player cannot progress.
Game has an ending message on number 99.

Minimal hardware requirements to launch:

2015+ year GPU or something like Vega8 modern integrated video card
Game use 500Mb VRAM.

Graphic shaders from this project my shadertoy link.

Tools that I made for this project I publish in my github project cube_ex_tools.