Let me save you some guessing. This one is basically the grandpappy of Minecraft and Terraria. You can dig tunnels, you can build stuff out of the dirt you've dug. There are minecarts to transport it in, multiple kinds of ore, the similarities go on.
This was before the era of early access games, or even commonplace over the air updates. Consequently they couldn't just continually upgrade the first clonk. Rather, when they made enough upgrades, a sequel was released. 3 was the latest version of the game designed for DOS.
In Clonk you take control of little Lemming-like creatures named Clonks. They can walk, jump, dig and throw. Your goal varies by level in singleplayer mode but there's also a multiplayer mode where the goal is to eliminate all enemy Clonks and their structures from the map.
Here you can see that, unlike Minecraft and Terraria, Clonk's terrain isn't made of giant cubes. Its made of pixels, so the tunnels you dig are more rounded and natural. It's not shown in this review but water even behaves like a fluid, with impressive particle physics for such an old game.
A look at the minecart and a castle. There are many different structure types for different purposes, making multiplayer largely about base building. I'd almost call it an RTS if you didn't have to manually control each Clonk. Certain tasks can be lightly automated though.
The tunnel I dug in a tutorial level. The goal was to get 3 gold, toss them all in the minecart and return it to the castle. The proper levels are much more complex and involve shooting cannons, draining a lake to kill sharks and more. It's one of those games with sufficient depth that you could play it for literal years and not get bored.
For that reason I give Clonk 3 an 8/10, docking a point for clunky, frustrating controls. They really, really get in the way and are the sole black mark on an otherwise stellar game.
Stay Cozy!