Tunneler

Tunneler, released in 1991, is a legendary piece of "bedroom programming" that became a massive hit in school computer labs and offices across the world.
Created by Joey deVilla (then a student at the University of Toronto), it is one of the most balanced and addictive two-player games ever made for DOS.
It’s essentially a high-stakes game of "underground hide-and-seek" with tanks.
Unlike most combat games where you can see your opponent, in Tunneler, you start on a split-screen. The entire map is solid earth, and you have no idea where the other player is.
Locate the enemy tank or their home base and destroy them. You have to tunnel through the dirt to move. As you move, you leave a trail (a tunnel) behind you.
If you cross into the other player's tunnel, you know they’ve been there, but you don't know which direction they went.
What made Tunneler so tense was the constant management of your resources:
- Energy Management: Your tank has a limited energy supply. Digging through dirt consumes energy quickly. Moving through pre-dug tunnels consumes less. If you run out of energy, your tank dies, and you lose the round.
- The Base: Your base is your lifeline. To refuel, you must return to your base. This creates a "leash" effect—you can only explore so far before you have to turn back, unless you're feeling lucky.
- Sonar/Radar: You have a "ping" or sonar ability that helps you locate the enemy base, but using it consumes a massive amount of energy.
- Combat: When you finally find the enemy, the game turns into a frantic shootout. One direct hit usually settles the score.

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