A drill sinks a vertical shaft kilometre by kilometre. Every kilometre it opens a gallery, and every gallery is a working face your crew hammers out by hand. The drill sets the pace. The crew turns that pace into ore.

Seven rock layers stand between the surface and the core, each harder than the last. Deep rock pays far more per stone and gives up far less per swing, so going deeper is always a trade rather than a straight upgrade. Fourteen ores, from plain anthracite to singularite.

Diggers are hired a full shift at a time and assigned by hand, gallery by gallery. A worked-out gallery yields nothing, so where people stand is a decision you keep making. Around five kilometres down, once the routine is yours, auto-shift unlocks and takes it off your hands.

Drill parts are built in three separate steps: buy the blueprint with credits, craft the part from ore and time, then fit it into one of the few slots the drill actually has. New slots appear with depth, so the interesting question is never what to build but what to leave off.

A sealed station at nine kilometres, specialists paid in resonance cores, supply chests, timed surges and a travelling trader. The mine runs while you are away, and the sky above the shaft keeps its own day and night.

Twenty-five kilometres to the core. Hand-drawn pixel art throughout.