Diggy

Diggy pairs a drill with a radar that reveals what's nearby before you tunnel into it, which turns digging from blind guesswork into a read on where the valuable gems and dangerous obstacles actually are before your drill ever reaches them.

Because the radar's range is limited, digging in short, deliberate bursts and rechecking it often catches hazards earlier than committing to one long tunnel in a single direction. Upgrades to drill speed and radar range compound on each other, a wider radar is only as useful as a drill fast enough to react to what it shows, so balancing spending between the two tends to outperform maxing one before touching the other. Dig Dug is the arcade classic that this same underground digging premise traces back to.